Modified thermoplastic norbornene polymer and process for the production thereof

ABSTRACT

A modified thermoplastic norbornene polymer obtained by graft-modifying a thermoplastic norbornene polymer selected from a ring-opening polymer of a norbornene monomer or a hydrogenated product thereof with at least one unsaturated compound selected from the group consisting of unsaturated epoxy compounds and unsaturated carboxylic compounds, and having a rate of graft modification of at least 10 mol % and a number average molecular weight (Mn) of 500 to 500,000, a production process thereof, and a crosslinking polymer composition comprising the modified thermoplastic norbornene polymer and a crosslinking agent.

TECHNICAL FIELD

[0001] The present invention relates to modified thermoplasticnorbornene polymers obtained by graft-modifying a ring-opening polymerof a norbornene monomer or a hydrogenated product thereof with anunsaturated epoxy compound or unsaturated carboxylic compound, and aproduction process thereof, and more particularly to modifiedthermoplastic norbornene polymers which are excellent in electricalproperties such as dielectric constant, adhesion property to othermaterials such as metals (metal foils, metallic wirings, etc.) andsilicon wafers, heat resistance, moisture resistance, etc., can beprepared into high-concentration solutions, and are also excellent inthe ability to uniformly disperse various kinds of compounding additivesin such a solution, and a production process thereof.

[0002] The modified thermoplastic norbornene polymers according to thepresent invention are suitable for use in electrical and electronicfields as impregnating resins for prepregs, sheets, interlayerinsulating films and the like making good use of these excellent variousproperties

BACKGROUND ART

[0003] With the rapid advancement of advanced information-orientedsociety in recent years, there is a strong demand for the speeding up ofinformation processing and the miniaturization of apparatus or devicesin a field of the electronic industry. In electronic parts used inelectrical apparatus and electronic equipment, such as semiconductors,ICs, hybrid ICs, printed boards, display devices and display parts,insulating materials having a sufficiently low dielectric constant in ahigh-frequency region are required for purpose of realizing the speedingup and miniaturization in the high-frequency region. In order to ensurehigh reliability over a long period of time, insulating materials alsoexcellent in heat resistance such as soldering heat resistance, andmoisture resistance are also required. Further, the speeding up ofinformation processing is pressed in a field of information processingapparatus such as computers and communication apparatus. In addition,their miniaturization and weight saving are required so as to beportable. In keeping with such requirements, it is strongly required ofcircuits installed in these apparatus to make circuit boards highperformance such as multi-layer structure, high precision and minuteprocessing.

[0004] In recent years, there has been developed a multi-chip module(MCM) for flip chip packaging, by which miniaturized and high-densitypackaging has been realized. In order to ensure high reliability over along period of time, an insulating material used in an interlayerinsulating film for this MCM is required to have, in addition to theabove required properties, sufficient adhesion property to substratessuch as silicon wafers, and conducting layers such as metal layers(metal foils, metallized films, etc.), since MCM is fabricated by layingmany insulating layers and conductive layers on one another on asubstrate such as a silicon wafer. In addition, since to be able to makea via diameter small by reduction in wiring pitch is require of MCM, itis required to impart photosensitivity to the insulating material inorder to make minute processing possible.

[0005] As insulating materials for MCM, there have heretofore beeninvestigated materials obtained by imparting photosensitivity to apolyimide resin or epoxy resin. However, the conventional photosensitivepolyimide resins are insufficient in electrical properties such asdielectric constant in a high-frequency region and also in moistureresistance and hence have involved a drawback that it is difficult tocope with the achievement of high reliability over a long period oftime. In the epoxy resins, it has been attempted to introduce aphotosensitive group such as an allyl group therein to impartphotosensitivity to the resins. However, such an attempt has involved adrawback that electrical properties, such as dielectric constant, of theresultant resins are deteriorated to a great extent, and their heatstability also become insufficient.

[0006] On the other hand, a circuit board is produced by impregnating areinforcing base material, for example, a glass cloth, with a resinvarnish, drying the varnish to form a sheet (prepreg) in a semi-curedstate, laying up a copper foil or outer copper-clad sheet, the prepreg,an inner copper-clad sheet, and the like in that order between mirrorplates and then hot-pressing the resultant laminate to completely curethe resin. As a resin material, there has heretofore been used a phenolresin, epoxy resin, polyimide resin, fluororesin, polybutadiene resin orthe like.

[0007] However, the dielectric constant of thermosetting resins such asthe phenol resin, epoxy resin and polyimide resin is generally as highas at least 4.0, and so their electrical properties are insufficient.Therefore, circuit boards making use of these thermosetting resins havebeen difficult to achieve the speeding up and high reliability ofarithmetic processing. On the other hand, circuit boards making use ofthermoplastic resins such as the fluororesins and polybutadiene resinsare poor in heat resistance and so may cause cracking and/ordelamination in some cases upon soldering or the like. In addition, suchresins have also been difficult to form a multi-layer structure due totheir poor dimensional stability.

[0008] Accordingly, in recent years, it has been proposed to usethermoplastic norbornene resins as insulating materials.

[0009] For example, Japanese Patent Application Laid-Open No. 34924/1987discloses a process comprising synthesizing a norbornene resin having anintrinsic viscosity [η] of 1.15 to 2.22 as measured at 135° C. indecalin by addition polymerization of a norbornene type cycloolefin andethylene, kneading the norbornene resin and a crosslinking aid, grindingthe resultant mixture, impregnating the ground mixture with a solutionof an organic peroxide, removing the solution and then press molding itto crosslink the resin.

[0010] However, this process has involved problems that the process iscomplicated, and besides it is difficult to prepare a high-concentrationsolution of the norbornene resin, and the organic peroxide and othercompounding additives are not uniformly dispersed. Accordingly, it isnecessary to prepare a low-concentration solution in order to produce aprepreg using a solution of the resin obtained by this process. When thereinforcing base material is impregnated with the low-concentrationsolution, however, it takes a long time to dry the solution until itbecomes tack-free at room temperature, and so the base material must beleft at rest so as not to deform in the meantime. Therefore, thisprocess involves a problem of poor productivity. In addition, variouskinds of compounding additives must be added according to various uses.However, such compounding additives cannot be uniformly dispersed in theresin solution due to the high viscosity of the solution, and there isalso an disadvantage that the resin solution and the compoundingadditives undergo phase separation from each other according to thekinds and compounding amounts of the compounding additives used. If thereinforcing base material is impregnated with the solutionphase-separated into 2 phases, any prepreg in which the individualcomponents are uniformly dispersed cannot be obtained. In addition, if acopper foil is laminated on the thus-obtained molding such as theprepreg, the resultant laminate has no sufficient peel strength andhence involves a problem of durability.

[0011] Japanese Patent Application Laid-Open No. 248164/1994 discloses aprocess in which a hydrogenated thermoplastic ring-opening norborneneresin, an organic peroxide, a crosslinking aid and a flame retardantsuch as brominated bisphenol are dispersed in a solvent, and casting isconducted using the resultant solution, or a reinforcing base materialis impregnated with the solution, and the solvent is then removed tocrosslinking the resin by heating, thereby producing a sheet prepreg orthe like. When the norbornene resin specifically disclosed in thispublication is used, however, it is difficult to make a solidsconcentration sufficiently high, and so productivity in a drying stepbecomes insufficient. In addition, such a process has involved a problemthat such a sheet or prepreg cannot be fully applied according to usefields, since the kinds and amounts of compounding additives which canbe uniformly dispersed are limited, and moreover its peel strength to acopper film is insufficient.

[0012] Japanese Patent Application Laid-Open No. 27412/1987 has proposedmodified cycloolefin copolymers obtained by grafting an unsaturatedepoxy compound such as allyl glycidyl ether on an addition copolymer ofethylene and a norbornene monomer. Japanese Patent Application Laid-OpenNo. 20692/1996 has proposed resin compositions comprising a cycloolefinresin having a carboxylic acid derivative type residue and aheat-crosslinking agent and/or a photo-crosslinking agent. JapanesePatent Application Laid-Open No. 259784/1996 has proposed resincompositions comprising an epoxy group-containing cycloolefin resin anda crosslinking agent. All of these resin materials have been reported tobe excellent in electrical properties, heat resistance, adhesionproperty, etc.

[0013] However, the modified polymers specifically disclosed in theseprior art documents are all insufficient in the rate of graftmodification. Therefore, they are insufficient in adhesion property toother materials such as metals and silicon wafers and moreover in heatresistance, and thus have involved a problem that deformation andcracking tend to occur in a solder reflowing step or a sputtering step.

DISCLOSURE OF THE INVENTION

[0014] It is an object of the present invention to provide modifiedthermoplastic norbornene polymers which are excellent in electricalproperties such as dielectric constant in a high-frequency region, heatresistance, moisture resistance and heat stability and also in adhesionproperty to other materials such as metals and silicon wafers, and aproduction process thereof.

[0015] Another object of the present invention is to providecrosslinking polymer compositions comprising an epoxy group-containingnorbornene polymer which is excellent in electrical properties such asdielectric constant in a high-frequency region, heat resistance,moisture resistance and heat stability and also in adhesion property toother materials such as metals and silicon wafers, and is also suitablefor compounding of a crosslinking agent.

[0016] A further object of the present invention is to provide modifiedthermoplastic norbornene polymers which are excellent in heatresistance, electrical properties such as dielectric constant, and peelstrength to metal foils, can be prepared into high-concentrationsolutions, and are also excellent in the ability to uniformly dispersevarious kinds of compounding additives in such a solution, a productionprocess thereof, and crosslinking polymer compositions comprising such amodified thermoplastic norbornene polymer and a crosslinking agent.

[0017] The present inventor has carried out an extensive investigationwith a view toward overcoming the above-described problems involved inthe prior art. As a result, it has been found that the above objects canbe achieved by graft-modifying a ring-opening polymer of a norbornenemonomer, which has a molecular weight within a specific range, or ahydrogenated product thereof with at least one unsaturated compoundselected from the group consisting of unsaturated epoxy compounds andunsaturated carboxylic compounds.

[0018] Of the modified thermoplastic norbornene polymers according tothe present invention, comparatively low-molecular weight polymershaving a rate of graft modification of at least 10 mol % and a numberaverage molecular weight (Mn) of 500 to 20,000 can be prepared intohigh-concentration solutions, and various compounding additives can beuniformly dispersed at a high concentration in such a solution. Sincesuch a solution is excellent in the ability to impregnate reinforcingbase materials and also good in film-forming property, prepregs andsheets can be produced by using a crosslinking polymer compositioncomprising the modified thermoplastic norbornene polymer and acrosslinking agent. In addition, laminates produced from the prepregs orsheets are excellent in heat resistance and dielectric constant, andmoreover a laminate excellent in peel strength to a metal layer can beprovided when the metal layer is laminated on such a prepreg or sheet.

[0019] Of the modified thermoplastic norbornene polymers according tothe present invention, comparatively high-molecular weight polymershaving a rate of graft modification of at least 10 mol % and a numberaverage molecular weight (Mn) exceeding 20,000 are excellent inelectrical properties such as dielectric constant in a high-frequencyregion, heat resistance, moisture resistance and heat stability, andalso in adhesion property to other materials such as metals and siliconwafers. Therefore, such polymers are particularly suitable for use asovercoats, interlayer insulating films and the like.

[0020] In addition, various crosslinking methods such as crosslinking byheat and crosslinking by light can be applied to the modifiedthermoplastic norbornene polymers according to the present invention byselecting the kind of a crosslinking agent used.

[0021] The present invention has been led to completion on the basis ofthese findings.

[0022] According to the present invention, there is thus provided amodified thermoplastic norbornene polymer obtained by graft-modifying athermoplastic norbornene polymer selected from a ring-opening polymer ofa norbornene monomer or a hydrogenated product thereof with at least oneunsaturated compound selected from the group consisting of unsaturatedepoxy compounds and unsaturated carboxylic compounds, wherein themodified polymer has a rate of graft modification of at least 10 mol %and a number average molecular weight (Mn) of 500 to 500,000.

[0023] According to the present invention, there is also provided aprocess for producing a modified thermoplastic norbornene polymer havinga rate of graft modification of at least 10 mol % and a number averagemolecular weight (Mn) of 500 to 500,000, the process comprising reactinga thermoplastic norbornene polymer selected from a ring-opening polymerof a norbornene monomer or a hydrogenated product thereof and having anumber average molecular weight (Mn) of 500 to 500,000 with at least oneunsaturated compound selected from the group consisting of unsaturatedepoxy compounds and unsaturated carboxylic compounds in the presence ofan organic peroxide.

[0024] According to the present invention, there is further provided acrosslinking polymer composition comprising a modified thermoplasticnorbornene polymer obtained by graft-modifying a thermoplasticnorbornene polymer selected from a ring-opening polymer of a norbornenemonomer or a hydrogenated product thereof with at least one unsaturatedcompound selected from the group consisting of unsaturated epoxycompounds and unsaturated carboxylic compounds, and having a rate ofgraft modification of at least 10 mol % and a number average molecularweight (Mn) of 500 to 500,000, and a crosslinking agent.

BEST MODE FOR CARRYING OUT THE INVENTION

[0025] Modified Thermoplastic Norbornene Polymer:

[0026] The modified thermoplastic norbornene polymers useful in thepractice of the present invention are those obtained by graft-modifyinga thermoplastic norbornene polymer having a number average molecularweight (Mn) of 500 to 500,000 with at least one unsaturated compoundselected from the group consisting of unsaturated epoxy compounds andunsaturated carboxylic compounds.

[0027] As the thermoplastic norbornene polymer, is used a ring-openingpolymer of a norbornene monomer or a hydrogenated product thereof. Thehydrogenated product of the ring-opening polymer of the norbornenemonomer is particularly preferred from the viewpoints of heatresistance, durability and electrical properties such as dielectricconstant.

[0028] (1) Norbornene Monomer:

[0029] No particular limitation is imposed on the norbornene monomer,ring-opening polymer of the norbornene monomer, and hydrogenated productthereof used in the present invention. Publicly known monomers andpolymers disclosed in, for example, Japanese Patent ApplicationLaid-Open Nos. 14882/1991 and 122137/1991, etc. may be used.

[0030] The norbornene monomers are publicly known compounds disclosed inthe above-described publications and Japanese Patent ApplicationLaid-Open Nos. 227424/1990 and 276842/1990, etc. Examples thereofinclude polycyclic hydrocarbons having a norbornene structure; alkyl-,alkenyl-, alkylidene- or aromatic-substituted derivatives thereof; theirderivatives substituted by a polar group such as a halogen, hydroxylgroup, ester group, alkoxy group, cyano group, amide group, imide groupor silyl group; alkyl-, alkenyl, alkylidene- or aromatic-substitutedderivatives of the norbornene monomers having such a polar group; etc.Of these, the polycyclic hydrocarbons having a norbornene structure, andalkyl-, alkenyl, alkylidene-or aromatic-substituted derivatives thereofare preferred in that they are particularly excellent in chemicalresistance and moisture resistance.

[0031] The typical norbornene monomers used in the present invention arecompounds represented by the formula (a):

[0032] wherein R¹ to R⁸ are independently a hydrogen atom, hydrocarbongroup, halogen atom, alkoxy group, ester group, cyano group, amidegroup, imide group, silyl group or hydrocarbon group substituted by apolar group (i.e., a halogen atom, alkoxy group, ester group, cyanogroup, amide group, imide group or silyl group), with the proviso thatat least two of R⁵ to R⁸ may be bonded to each other to form a monocycleor polycycle, the monocycle or polycycle may have carbon-carbon doublebond(s) or be in the form of an aromatic ring, and R⁵ and R⁶, or R⁷ andR⁸ may form an alkylidene group.

[0033] Examples of the halogen atom in the formula (a) include fluorine,chlorine, bromine and iodine atoms. Examples of the hydrocarbon groupinclude alkyl groups having 1 to 20 carbon atoms, preferably 1 to 10carbon atoms, alkenyl groups having 2 to 20 carbon atoms, preferably 2to 10 carbon atoms, cycloalkyl groups having 3 to 15 carbon atoms,preferably 3 to 8 carbon atoms, and aryl groups having 6 to 12 carbonatoms, preferably 6 to 8 carbon atoms. Examples of the hydrocarbon groupsubstituted by a polar group include halogenated alkyl groups having 1to 20 carbon atoms, preferably 1 to 10 carbon atoms. The alkylidenegroup is preferably not substituted by any polar group, since themoisture resistance of the resulting polymer is highly enhanced. Thenumber of carbon atoms thereof is generally within a range of 1 to 20,preferably 1 to 10.

[0034] Specific examples of the alkyl groups include methyl, ethyl,n-propyl, isopropyl, n-butyl, t-butyl, n-amyl, n-hexyl and decyl groups.Specific examples of the alkenyl groups include vinyl, propenyl,butenyl, pentenyl and hexenyl groups. Specific examples of the aromaticgroups include phenyl, tolyl, xylyl, biphenyl and naphthyl groups.Specific examples of the alkylidene group include methylidene,ethylidene, propylidene and isopropylidene groups. Examples of the estergroup include alkyl ester groups.

[0035] In the formula (a), each of R¹ to R⁴ is preferably a hydrogenatom or hydrocarbon group when high moisture resistance is required. Atleast two of R⁵ to R⁸ may be bonded to each other to form a monocycle orpolycycle, and the monocycle or polycycle may have carbon-carbon doublebond(s) or be in the form of an aromatic ring. In this case, themonocycle or polycycle may have such a substituent group (hydrocarbongroup, polar group or hydrocarbon group substituted by the polar group)as described above. In this case, however, the monocycle or polycyclepreferably has no polar group when high moisture resistance is required.

[0036] As preferable examples of the norbornene monomers represented bythe formula (a), may be mentioned compounds represented by the formula(a1):

[0037] In the formula (a1), R⁹ to R²⁰ are independently a hydrogen atom,hydrocarbon group, halogen atom, alkoxy group, ester group (for example,alkyl ester group), cyano group, amide group, imide group, silyl groupor hydrocarbon group substituted by a polar group (i.e., a halogen atom,alkoxy group, ester group, cyano group, amide group, imide group orsilyl group). When high moisture resistance is required of the resultingpolymer, each of these groups is a hydrogen atom or hydrocarbon group.However, at least two of R to R may be bonded to each other to form amonocycle or polycycle, and the monocycle or polycycle may havecarbon-carbon double bond(s) or be in the form of an aromatic ring. R¹⁷and R¹⁸, or R¹⁹ and R²⁰ may form an alkylidene group. It goes withoutsaying that the monocycle, polycycle or aromatic ring may have such asubstituent group (hydrocarbon group, polar group or hydrocarbon groupsubstituted by the polar group) as described above. In this case,however, such a cycle or ring preferably has no polar group when highmoisture resistance is required. Specific examples of these substituentsare the same as described above.

[0038] As other preferable examples of the norbornene monomersrepresented by the formula (a), may be mentioned compounds representedby the formula (a2):

[0039] In the formula (a2), m is 0, 1 or 2. When m is 0, a cyclopentanering is formed. R²¹ to R³² are independently a hydrogen atom,hydrocarbon group, halogen atom, alkoxy group, ester group (for example,alkyl ester group), cyano group, amide group, imide group, silyl groupor hydrocarbon group substituted by a polar group (i.e., a halogen atom,alkoxy group, ester group, cyano group, amide group, imide group orsilyl group). When high moisture resistance is required of the resultingpolymer, each of these groups is a hydrogen atom or hydrocarbon group.However, at least two of R²⁹ to R³² may be bonded to each other to forma monocycle or polycycle, and the monocycle or polycycle may havecarbon-carbon double bond(s) or be in the form of an aromatic ring. R²⁹and R³⁰, or R³¹ and R³² may form an alkylidene group, or R³⁰ and R³¹ maybe bonded to each other to form a double bond between 2 carbon atoms towhich R³⁰ and R³¹ are bonded, respectively. It goes without saying thatthe monocycle, polycycle or aromatic ring may have such a substituentgroup (hydrocarbon group, polar group or hydrocarbon group substitutedby the polar group) as described above. In this case, however, such acycle or ring preferably has no polar group when high moistureresistance is required. Specific examples of these substituents are thesame as described above.

[0040] Specific examples of the norbornene monomers includebicyclo[2.2.1]hept-2-ene derivatives,tetracyclo-[4.4.0.1^(2,5)1^(7,10)]-3-dodecene derivatives,hexacyclo-[6.6.1.1^(3,6).0^(10,13).0^(2,7).0^(9,14)]-4-heptadecenederivatives, octacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-docosene derivatives,pentacyclo[6.6.1.1^(3,6).0^(2,7)0^(9,14)]-4-hexadecene derivatives,heptacyclo-5-eicosene derivatives, heptacyclo-5-heneicosene derivatives,tricyclo[4.3.0.1^(2,5)]-3-decene derivatives,tricyclo[4.4.0.1^(2,5)]-3-undecene derivatives,pentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecene derivatives,pentacyclopentadecadiene derivatives,pentacyclo[7.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-pentadecene derivatives,heptacyclo[8.7.0.1^(3,6).1^(10,17).1^(12,15).0^(2,7).0^(11,16)]-4-eicosenederivatives,nonacyclo[10.9.1.1^(4,7).1^(13,20).1^(15,18)0^(3,8).0^(2,10).0^(12,21).0^(14,19)]-5-pentacosenederivatives, pentacyclo[8.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-hexadecenederivatives,heptacyclo[8.8.0.1^(4,7),1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicosenederivatives,nonacyclo-[10.10.1.1^(5,8).1^(14,21).1^(16,19).0^(2,11).0^(4,9).0^(13,22).0^(15,20)]-5-hexacosenederivatives, 1,4-methano-1,4,4a,9a-tetrahydrofluorene derivatives,1,4-methano-1,4,4a,5,10,10a-hexahydro-anthracene derivatives andcyclopentadiene-acenaphthylene adducts.

[0041] More specifically, examples of the norbornene monomers includebicyclo[2.2.1]hept-2-ene derivatives such as bicyclo[2.2.1]hept-2-ene,6-methylbicyclo[2.2.1]hept-2-ene, 5,6-dimethylbicyclo[2.2.1]hept-2-ene,1-methyl-bicyclo[2.2.1]hept-2-ene, 6-ethylbicyclo[2.2.1]hept-2-ene,6-n-butylbicyclo[2.2.1]hept-2-ene, 6-isobutylbicyclo-[2.2.1]hept-2-eneand 7-methylbicyclo[2.2.1]hept-2-ene;tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene derivatives such astetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-methyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-propyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-butyl-tetracyclo[4.4.0.1^(2,5).1 ^(7,10)]-3-dodecene,8-isobutyltetracyclo[4.4.0.1^(2,5).1^(7,10) ]-3-dodecene,8-hexyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-cyclohexyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-stearyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,5,10-dimethyltetracyclo-[4.4.0.1^(2,5).1^(7,10)-3-dodecene,2,10-dimethyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,2,10-dimetehyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8,9-dimethyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethyl-9-9—methyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,11,12-dimethyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,2,7,9-trimethyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,9-ethyl-2,7-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,9-isobutyl-2,7-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,9,11,12-trimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,9-ethyl-11,12-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,9-isobutyl-11,12-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,5,8,9,10-tetramethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethylidene-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethylidene-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethylidene-9-isopropyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-ethylidene-9-butyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-n-propylidene-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-n-propylidene-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-n-propylidene-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-n-propylidene-9-isopropyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-n-propylidene-9-butyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-isopropylidenetetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-isopropylidene-9-methyltetracyclo-[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-isopropylidene-9-ethyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-isopropylidene-9-isopropyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-iso-propylidene-9-butyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-chlorotetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-bromo-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-fluorotetracyclo-[4.4.0.125.1^(7,10)]-3-dodecene and8,9-dichlorotetracyclo-[4.4.0.1^(2,5).1^(7,10) ]-3-dodecene;hexacyclo6.6.1.1^(3,6).1^(10,13).0^(2,7).^(9,14)]-4-heptadecenederivatives such ashexacyclo-[6.6.1.1^(3,6).1^(10,13).0^(2,7).0^(9,14)]-4-heptadecene,12-methyl-hexacyclo[6.6.1.1^(3,6).1^(10,13).0^(2,7).0^(9,14)]-4-heptadecene,12-ethylhexacyclo[6.6.1.1^(3,6).1^(10,13).0^(2,7).0^(9,14)]-4-heptadecene,12-isobutylhexacyclo[6.6.1.1^(3,6).1^(10,13).0^(2,7).0^(9,14)]-4-heptadeceneand1,6,10-trimethyl-12-isobutylhexacyclo-[6.6.1.1^(3,6).1^(10,13).0^(2,7).0^(9,14)]-4-heptadecene;octacyclo-[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-docosenederivatives such asoctacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-docosene,15-methyloctacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-docoseneand15-ethyloctacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-docosene;pentacyclo[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene derivatives suchas pentacyclo-[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene,1,3-dimethylpentacyclo-[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene,1,6-dimethylpentacyclo-[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene and15,16-dimethylpenta-cyclo[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene;heptacyclo-5-heneicosene derivatives or heptacyclo-5-heneicosenederivatives such asheptacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-eicoseneandheptacyclo[8.8.0.1^(2,9).1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicosene;tricyclo[4.3.0.1^(2,5) ]-3-decene derivatives such astricyclo[4.3.0.1^(2,5) ]-3-decene, 2-methyltricyclo[4.3.0.1^(2,5)]-3-decene and 5-methyltricyclo-[4.3.0.1^(2,5)]-3-decene;tricyclo[4.3.0.1^(2,5) ]-3-undecene derivatives such astricyclo[4.3.0.1^(2,5) ]-3-undecene and 10-methyltricyclo[4.3.0.1^(2,5)]-3-undecene; pentacyclo-[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecenederivatives such aspentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecene,1,3-dimethyl-pentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecene,1,6-dimethyl-pentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadeceneand14,15-dimethylpentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecene;diene compounds such aspentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4,10-pentadecadiene;pentacyclo[7.4.0.1^(2,5).1^(9,12).0^(8,13) ]-3-penta-decene derivativessuch as pentacyclo[7.4.0.1^(2,5).1^(9,12).0^(8,13) ]-3-pentadecene andmethyl-substituted pentacyclo-[7.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-pentadecene;heptacyclo-[8.7.0.1^(3,6).1^(10,17).1^(12,15).0^(2,7).0^(11,16)]-4-eicosenederivatives such asheptacyclo-[8.7.0.1^(3,6).1^(10,17).1^(12,15).0^(2,7).0^(11,16)]-4eicosene and dimethyl-substitutedheptacyclo-[8.7.0.1^(3,6).1^(10,17).1^(12,15).0^(2,7).0^(11,16)]-4-eicosene;nonacyclo-[10.9.1.1^(4,7).1^(13,20).1^(15,18).0^(3,8).0^(2,10).0^(12,21).0^(14,19)]-5-pentacosenederivatives such asnonacyclo[10.9.1.1^(4,7).1^(13,20).1^(15,18).0^(3,8).0^(2,10).0^(12,21).0^(14,19)]-5-pentacoseneand trimethyl-substitutednonacyclo[10.9.1.1^(4,7).1^(13,20).1^(15,18).0^(3,8).0^(2,10).0^(12,21).0^(14,19)]-5pentacosene; pentacyclo[8.4.0.1^(2,5).1^(9,12). 0^(8,13)]-3-hexadecenederivatives such as pentacyclo[8.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-hexadecene, 11-methylpentacyclo[8.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-hexadecene, 11-ethylpentacyclo[8.4.0.1^(2,5).1^(9,12).0^(8,13)]-3-hexadecene and10,11-dimethylpentacyclo[8.4.0.1^(2,5).1^(9,12). 0^(8,13)]-3-hexadecene;heptacyclo-[8.8.0.1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicosenederivatives such asheptacyclo-[8.8.0.1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicosene,15-methyl-heptacyclo[8.8.0.1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicoseneandtrimethylheptacyclo[8.8.0.1^(4,7).1^(11,18).1^(13,16).0^(3,8).0^(12,17)]-5-heneicosene;nonacyclo[10.10.1.1^(5,8).1^(14,21).1^(16,19).0^(2,11).0^(4,9).0^(13,22).0^(15,20)]-6-hexacosene derivatives such asnonacyclo-[10.10.1.1^(5,8).1^(14,21).1^(16,19).0^(2,11).0^(4,9).0^(13,22).0^(15,20)]-6-hexacosene;pentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4,11-pentadecadiene,methyl-substitutedpentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4,11-penta-decadiene,trimethyl-substitutedpentacyclo[4.7.0.1^(2,5).0^(8,13).1^(9,12)]-3-pentadecene,pentacyclo[4.7.0.1^(2,5).0^(8,13).1^(9,12)]-3,10-pentadecadiene,methyl-substitutedpentacyclo-[4.7.0.1^(2,5).0^(8,13).1^(9,12)]-3,10-pentadecadiene,methyl-substituted pentacyclo[4.7.0.1^(2,5).0^(8,13).1^(9,12)]-3,10-pentadecadiene, methyl-substitutedheptacyclo-[7.8.0.1^(3,6).0^(2,7).1^(10,17).0^(11,16).1^(12,15)]-4-eicosene,trimethyl-substitutedheptacyclo[7.8.0.1^(3,6).0^(2,7).1^(10,17).0^(11,16).1^(12,15)]-4-eicosene,tetramethyl-substitutedheptacyclo-[7.8.0.1^(3,6).0^(2,7).1^(10,17).0^(11,16).1^(12,15)]-4-eicosene,tricyclo-[4.3.0.1^(2,5)]-3,7-decadiene (i.e., dicyclopentadiene),2,3-dihydrodicyclopentadiene, 5-phenyl-bicyclo[2.2.1]hept-2-ene (i.e.,5-phenyl-2-norbornene), 5-methyl-5-phenyl-bicyclo[2.2.]hept-2-ene,5-benzyl-bicyclo[2.2.1]hept-2-ene, 5-tolylbicyclo[2.2.1]hept-2-ene,5-(ethylphenyl)-bicyclo[2.2.1]hept-2-ene,5-(isopropylphenyl)-bicyclo-[2.2.1]hept-2-ene,8-phenyl-tetracyclol[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-methyl-8-phenyl-tetracyclolo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-benzyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-tolyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-(ethyl-phenyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-(iso-propylphenyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8,9-diphenyl-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-(biphenyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-(β-naphthyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,8-(α-naphthyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3—dodecene,8-(anthracenyl)-tetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene,11-phenyl-hexacyclo[6.6.1.1^(3,6).0^(2,7)0^(9,14) ]-4-heptadecene,6-(α-naphthyl)-bicyclo[2.2.1]-hept-2-ene,5-(anthracenyl)-bicyclo[2.2.1]hept-2-ene,5-(biphenyl)-bicyclo[2.2.1]-hept-2-ene,5-(β-naphthyl)-bicyclo[2.2.1]hept-2-ene,5,6-diphenyl-bicyclo[2.2.1]hept-2-ene, 9-(2-norbornen-5-yl)-carbazole,1,4-methano-1,4,4a,4b,5,8,8a,9a-octahydro-fluorene and derivativesthereof; 1,4-methano-1,4,4a,9a-tetrahydrofluorene and derivativesthereof, such as 1,4-methano-1,4,4a,9a-tetrahydrofluorene,1,4-methano-8-methyl-1,4,4a,9a-tetrahydrofluorene,1,4-methano-8-chloro-1,4,4a,9a-tetrahydrofluorene and1,4-methano-8-bromo-1,4,4a,9a-tetrahydrofluorene;1,4-methano-1,4,4a,9a-tetrahydrobenzofuran and derivatives thereof;1,4-methano-1,4,4a,9a-tetrahydrocarbazole and derivatives thereof, suchas 1,4-methano-1,4,4a,9a-tetrahydrocarbazole and1,4-methano-9-phenyl-1,4,4a,9a-tetrahydrocarbazole;1,4-methano-1,4,4a,5,10,10a-hexahydroanthracene and derivatives thereof,such as 1,4-methano-1,4,4a,5,10,10a-hexahydroanthracene;7,10-methano-6b,7,10,10a-tetrahydro-fluoracene and derivatives thereof;and compounds obtained by further adding cyclopentadiene tocyclopentadiene-acenaphthylene adducts,11,12-benzopentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]-4-pentadecene,11,12-benzopentacyclo[6.6.1.1^(3,6).0^(2,7).0^(9,14)]-4-hexadecene,14,15-benzoheptacyclo[8.7.0.1^(2,9).1^(4,7).1^(11,17).0^(3,8).0^(12,16)]-5-eicosene,and cyclopentadiene-acenaphthylene adducts.

[0042] These norbornene monomers may be used either singly or in anycombination thereof.

[0043] For example, α-olefins such as 1-butene, 1-hexene,3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene,4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene,4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene,1-decene, 1-dodecne, 1-tetradecene, 1-hexadecene, 1-octadecene and1-eicosene; non-conjugated diolefins such as 1,4-hexadiene; etc. may beused within a range of up to about 10 mol % as a molecular weightmodifier.

[0044] (2) Ring-opening Polymerization:

[0045] The ring-opening polymer of the norbornene monomer can beobtained by subjecting the norbornene monomer to ring-openingpolymerization, generally, at a polymerization temperature of −50° C. to100° C. and a polymerization pressure of 0 to 50 kg/cm in a solvent orwithout using any solvent using, as a ring-opening polymerizationcatalyst, a catalyst system composed of a halide, nitrate oracetylacetone compound of a metal such as ruthenium, rhodium, palladium,osmium, iridium or platinum, and a reducing agent; a catalyst systemcomposed of a halide or acetylacetone compound of a metal such astitanium, vanadium, zirconium, tungsten or molybdenum, and anorganoaluminum compound; or the like.

[0046] A third component such as molecular oxygen, alcohol, ether,peroxide, carboxylic acid, acid anhydride, acid chloride, ester, ketone,nitrogen-containing compound, sulfur-containing compound,halogen-containing compound, molecular iodine or any other Lewis acidcan be added to the catalyst system to improve polymerization activityand selectivity of ring-opening polymerization.

[0047] (3) Hydrogenation:

[0048] The hydrogenated product of the ring-opening polymer of thenorbornene monomer can be obtained by hydrogenating the ring-openingpolymer with hydrogen in the presence of a hydrogenation catalyst inaccordance with a method known per se in the art.

[0049] Examples of the hydrogenation catalyst include catalysts composedof a combination of a transition metal compound and an alkyl metalcompound, for example, combinations of cobalt acetate/triethylaluminum,nickel acetylacetonate/triisobutylaluminum, titanocenedichloride/n-butyllithium, zirconocene dichloride/sec-butyllithium,tetrabutoxytitanate/dimethylmagnesium, etc.

[0050] The hydrogenation reaction is generally carried out in an inertorganic solvent. The organic solvent is preferably a hydrocarbon solventbecause it has the excellent ability to dissolve a hydrogenated productformed therein. A cyclic hydrocarbon solvent is more preferred. Examplesof such a hydrocarbon solvent include aromatic hydrocarbons such asbenzene and toluene; aliphatic hydrocarbons such as n-pentane andhexane; alicyclic hydrocarbons such as cyclohexane and decalin; andethers such as tetrahydrofuran and ethylene glycol dimethyl ether. Atleast two of these solvents may also be used in combination. The solventmay be generally the same as that used in the polymerization reaction,and so it is only necessity to add the hydrogenation catalyst to thepolymerization reaction mixture as it is, so as to conduct the reaction.

[0051] The norbornene polymers used in the present invention preferablyhave high weather resistance and resistance to deterioration by light.Therefore, it is preferred that generally at least 95%, preferably atleast 98%, more preferably at least 99% of the unsaturated bonds in themain chain structures of the ring-opening polymers should be saturated.The unsaturated bonds in an aromatic ring structure may be hydrogenated.However, it is desirable from the viewpoint of heat resistance thatgenerally at least 20%, preferably at least 30%, more preferably atleast 40% of the unsaturated bonds in the aromatic ring structure shouldremain unhydrogenated. The unsaturated bond in the main chain structureand the unsaturated bonds in the aromatic ring structure can bedistinguishably identified by ¹H-NMR analysis.

[0052] In order to mainly hydrogenate the unsaturated bond in the mainchain structure, it is desirable that the hydrogenation reaction shouldbe conducted at a temperature of generally −20° C. to 120° C.,preferably 0 to 100° C., more preferably 20 to 80° C. under a hydrogenpressure of generally 0.1 to 50 kg/cm², preferably 0.5 to 30 kg/cm²,more preferably 1 to 20 kg/cm².

[0053] (4) Thermoplastic Norbornene Polymer:

[0054] The thermoplastic norbornene polymers used in the presentinvention are ring-opening polymers of norbornene monomers orhydrogenated products thereof. Such a thermoplastic norbornene polymercan be typically obtained by subjecting a norbornene monomer representedby the formula (a) to ring-opening polymerizetion and hydrogenating theresultant polymer as needed.

[0055] As specific examples of such a polymer, may be mentioned polymershaving repeating units represented by the formula (A):

[0056] In the formula (A), R¹ to R⁸ have the same meanings as defined inthe formula (a). However, in the case where the carbon-carbon doublebond in the main chain is hydrogenated, non-conjugated unsaturated bondsin side chains are also hydrogenated if any. When aromatic rings arepresent in side chains, it is desirable from the viewpoint of heatresistance that part or the whole of unsaturated bonds in the aromaticrings should remain unhydrogenated even after the hydrogenation.

[0057]. . . in the formula (A) means either a single bond or a doublebond. When the rate of hydrogenation is as high as at least 99%, thecarbon-carbon double bond in the main chain is converted into a singlebond. When the hydrogenation is partially conducted, the hydrogenatednorbornene polymer is in a state that a single bond and a double bondcoexist in the main chain.

[0058] When the norbornene monomer represented by the formula (a1) issubjected to ring-opening polymerization, and the resultant polymer ishydrogenated as needed, a polymer having repeating units represented bythe formula (A1):

[0059] is obtained.

[0060] In the formula (A1), R⁹ to R²⁰ have the same meanings as definedin the formula (a1). However, in the case where the carbon-carbon doublebond in the main chain is hydrogenated, non-conjugated unsaturated bondsin side chains are also hydrogenated if any. When aromatic rings arepresent in side chains, it is desirable from the viewpoint of heatresistance that part or the whole of unsaturated bonds in the aromaticrings should remain unhydrogenated even after the hydrogenation. . . .in the formula (A1) means either a single bond or a double bond.

[0061] When the norbornene monomer represented by the formula (a2) issubjected to ring-opening polymerization, and the resultant polymer ishydrogenated as needed, a polymer having repeating units represented bythe formula (A2):

[0062] is obtained.

[0063] In the formula (A2), R²¹ to R³² have the same meanings as definedin the formula (a2). However, in the case where the carbon-carbon doublebond in the main chain is hydrogenated, non-conjugated unsaturated bondsin side chains are also hydrogenated if any. Then aromatic rings arepresent in side chains, it is desirable from the viewpoint of heatresistance that part or the whole of unsaturated bonds in the aromaticrings should remain unhydrogenated even after the hydrogenation in theformula (A2) means either a single bond or a double bond.

[0064] The molecular weight of the thermoplastic norbornene polymer usedis 500 to 500,000, preferably 3,000 to 300,000, more preferably 5,000 to250,000 when expressed by a number average molecular weight (Mn) interms of polystyrene as measured by gel permeation chromatography (GPC)using toluene as a solvent or when expressed by a number averagemolecular weight (Mn) in terms of polyisoprene as measured by GPC usingcyclohexane as a solvent if the polymer is insoluble in toluene.

[0065] If the number average molecular weight (Mn) of the norbornenepolymer is extremely low, the mechanical strength of the polymer becomespoor. If the molecular weight is extremely high on the other hand, therate of graft modification with the unsaturated compound selected fromthe group consisting of unsaturated epoxy compounds and unsaturatedcarboxylic compounds cannot be heightened, and the processability of theresulting modified polymer is also deteriorated.

[0066] No particular limitation is imposed on the molecular weightdistribution of the thermoplastic norbornene polymer. However, it ispreferred that its ratio (Mw/Mn) of the weight average molecular weight(Mw) to the number average molecular weight (Mn) in terms of polystyreneas measured by GPC using toluene as a solvent be generally 4.0 or lower,preferably 3.0 or lower, more preferably 2.5 or lower, since themechanical strength of the polymer is highly enhanced.

[0067] The glass transition temperature (Tg) of the thermoplasticnorbornene polymer may be suitably selected as necessary for the endapplication intended. However, it is generally about 50 to 200° C. asmeasured by a differential scanning calorimeter (DSC). The thermoplasticnorbornene polymer preferably has a high glass transition temperaturebecause deterioration of mechanical strength of the polymer particularlyin a region of high temperatures such as a temperature upon packaging ofelectronic parts and the like, and a reliability testing temperature issuppressed, and its viscosity characteristics also become excellent.Even when the glass transition temperature is comparatively low,however, the heat resistance can be sufficiently enhanced by using themodified polymer in combination with a crosslinking agent to form acrosslinked polymer.

[0068] (5) Graft Modification:

[0069] The graft monomer used in the present invention is an unsaturatedcompound selected from the group consisting of unsaturated epoxycompounds and unsaturated carboxylic compounds.

[0070] Examples of the unsaturated epoxy compounds include glycidylesters such as glycidyl acrylate, glycidyl methacrylate and glycidylp-styrylcarboxylate; monoglycidyl esters or polyglycidyl esters ofunsaturated polycarboxylic acids such asendo-cis-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylic acid andendo-cis-bicyclo[2,2,1]-hept-5-ene-2-methyl-2,3-dicarboxylic acid;unsaturated glycidyl ethers such as allyl glycidyl ether, 2-methyl-allylglycidyl ether, glycidyl ether of o-allylphenol, glycidyl ether ofm-allylphenol and glycidyl ether of p-allylphenol; and2-(o-vinylphenyl)ethylene oxide, 2-(p-vinylphenyl)ethylene oxide,2-(o-allylphenyl)ethylene oxide, 2-(p-allylphenyl)ethylene oxide,2-(o-vinyl-phenyl)propylene oxide, 2-(p-vinylphenyl)propylene oxide,2-(o-allylphenyl)propylene oxide, 2-(p-allylphenyl)-propylene oxide,p-glycidylstyrene, 3,4-epoxy-1-butene, 3,4-epoxy-3-methyl-1-butene,3,4-epoxy-1-pentene, 3,4-epoxy-3-methyl-1-pentene, 5,6-epoxy-1-hexene,vinylcyclohexene monoxide and allyl-2,3-epoxycyclopentyl ether. Ofthese, the allyl glycidyl esters and allyl glycidyl ethers arepreferred, with the allyl glycidyl ethers being particularly preferred.

[0071] As the unsaturated carboxylic compounds, may be used unsaturatedcarboxylic acids or derivatives thereof. As examples of such unsaturatedcarboxylic: acids, may be mentioned acrylic acid, maleic acid, fumaricacid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonicacid, isocrotonic acid and nadic acid(endo-cis-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxyic acid). As examples ofderivatives of the above-described unsaturated carboxylic acids, may bementioned unsaturated carboxylic acid anhydrides, unsaturated carboxylicacid halides, unsaturated carboxylic acid amides, unsaturated carboxylicacid imides and ester compounds of unsaturated carboxylic acids. Asspecific examples of such derivatives, may be mentioned malenylchloride, maleimide, maleic anhydride, citraconic anhydride, monomethylmaleate, dimethyl maleate and glycidyl maleate. Of these, theunsaturated dicarboxylic acids or acid anhydrides thereof are preferred,with maleic acid and nadic acid or acid anhydrides thereof beingparticularly preferred.

[0072] These graft monomers may be used either singly or in anycombination thereof.

[0073] The modified thermoplastic norbornene polymers according to thepresent invention can be produced by subjecting such a graft monomer asdescribed above and the thermoplastic norbornene polymer to graftmodification by using any of various processes conventionally known.Examples of the processes include (1) a process comprising melting athermoplastic norbornene polymer and adding a graft monomer to the meltto graft polymerize them, and (2) a process comprising dissolving athermoplastic norbornene polymer in a solvent and then adding a graftmonomer to the solution to graft copolymerize them. In addition, methodsfor producing the modified thermoplastic norbornene polymers include amethod in which a graft monomer is mixed with an unmodifiedthermoplastic norbornene polymer in such a manner that the rate of graftmodification of the resulting polymer reaches the desired rate, therebymodifying the polymer, and a method in which a graft-modifiedthermoplastic norbornene polymer having a high rate of graftmodification is prepared in advance, and the modified thermoplasticnorbornene polymer having the high rate of graft modification is dilutedwith an unmodified thermoplastic norbornene polymer to produce agraft-modified thermoplastic norbornene polymer having the desired rateof graft modification. In the present invention, any production processor method may be adopted.

[0074] In order to efficiently graft copolymerize the graft monomer, itis generally preferred to carry out a reaction in the presence of aradical initiator.

[0075] As the radical initiator, for example, organic peroxides, organicperesters, etc. may be preferably used. As specific examples of suchradical initiators, may be mentioned benzoyl peroxide, dichlorobenzoylperoxide, dicumyl peroxide, di-tert-butyl peroxide,2,5-dimethyl-2,5-di(tert-butylperoxybenzoate)hexyne-3,1,4-bis(tert-butyl peroxyisopropyl)benzene,lauroyl peroxide, tert-butyl peracetate, 2,5-di(tert-butylperoxy)hexyne-3,2,5-dimethyl-2,5-di(tert-butyl peroxy)hexarle,tert-butyl perbenzoate, tert-butyl peracetate, tert-butylperisobutyrate, tert-butyl per-sec-octoate, tert-butyl perpivalate,cumyl perpivalate and tert:-butyl perdiethylacetate.

[0076] In the present invention, azo compounds may also be used asradical initiators. As specific examples of the azo compounds, may bementioned azobisisobutyronitrile and dimethyl azoisobutyrate.

[0077] Of these, benzoyl peroxide, and dialkyl peroxides such as dicumylperoxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3,2,5-dimethyl-2,5-di(tert-butyl peroxy)hexane and1,4-bis(tert-butyl peroxyisopropyl)benzene are preferably used as theradical initiators.

[0078] These radical initiators may be used either singly or in anycombination thereof. A proportion of the radical initiator used isgenerally within a range of 0.001 to 10 parts by weight, preferably 0.01to 5 parts by weight, more preferably 0.1 to 2.5 parts by weight per 100parts by weight of the unmodified thermoplastic norbornene polymer.

[0079] No particular limitation is imposed on the graft-modifyingreaction, and the reaction may be carried out in accordance with amethod known per se in the art. The reaction is conducted at atemperature of generally 0 to 400° C., preferably 60 to 350° C. Thereaction time is generally within a range of 1 minute to 24 hours,preferably 30 minutes to 10 hours.

[0080] (6) Modified Thermoplastic Norbornene Polymer:

[0081] The molecular weight of the modified thermoplastic norbornenepolymer is within a range of-500 to 500,000, preferably 3,000 to300,000, more preferably 5,000 to 250,000 when expressed by a numberaverage molecular weight (Mn) in terms of polystyrene as measured by gelpermeation chromatography (GPC) using toluene as a solvent or whenexpressed by a number average molecular weight (Mn) in terms ofpolyisoprene as measured by GPC using cyclohexane as a solvent if themodified thermoplastic norbornene polymer is insoluble in toluene.

[0082] When the modified thermoplastic norbornene polymer is used as ahigh-concentration solution, a composition with a great amount ofcompounding additives or an impregnating solution for reinforcing basematerials, its number average molecular weight (Mn) is controlled withina range of generally 500 to 20,000, preferably 3,000 to 20,000, morepreferably 5,000 to 19,500.

[0083] On the other hand, when the modified thermoplastic norbornenepolymer is used in application fields such as an interlayer insulatingfilm, its number average molecular weight (Mn) is generally controlledso as to exceed 20,000, and its upper limit is at most 500,000,preferably at most 300,000, more preferably at most 250,000.

[0084] If the number average molecular weight (Mn) of the modifiedthermoplastic norbornene polymer is extremely low, the mechanicalstrength of the polymer becomes poor. If the molecular weight isextremely high on the other hand, the viscosity of the modifiedthermoplastic norbornene polymer when dissolved in a solvent isincreased, and so the concentration of solids including compoundingadditives cannot be heightened, and its processability is alsodeteriorated. It is hence not preferred to use the modifiedthermoplastic norbornene polymer having such an extremely low or highmolecular weight.

[0085] The molecular weight distribution of the modified thermoplasticnorbornene polymer may be suitably selected as necessary for the endapplication intended. However, it is preferred that its ratio (Mw/Mn) ofthe weight average molecular weight (Mw) to the number average molecularweight (Mn) as measured by GPC under the above-described conditions begenerally 4.0 or lower, preferably 3.5 or lower, more preferably 2.5 orlower, since the mechanical strength of the polymer is particularlyhigh. In mane cases, Mw/Mn is 2.0 or lower.

[0086] The rate of graft modification of the modified thermoplasticnorbornene polymer used in the present invention is suitably selected asnecessary for the end application intended. However, it is generallywithin a range of 10 to 100 molt, preferably 15 to 50 molt, morepreferably 15 to 35 molt based on the total number of monomer units inthe polymer. The modified thermoplastic norbornene polymer the rate ofgraft modification of which falls within this range is preferred becausethe electrical properties such as dielectric constant, adhesion propertyto metals, silicon wafers and the like, ability to uniformly dispersevarious kinds of compounding additives therein, etc. are balanced withone another at a high level. If the rate of graft modification is toolow, its adhesion property to other materials such as metals and siliconwafers becomes deteriorated, and in its turn, the heat resistance,durability and the like also become deteriorated.

[0087] The rate of graft modification is represented by the followingequation (1):

Rate of graft modification (mol %)=(X/Y)×100  (1)

[0088] wherein

[0089] X: the total number of moles of the modifying group introducedinto the polymer by grafting of the unsaturated compound; and

[0090] Y: the total number of monomer units in the polymer (weightaverage molecular weight of the polymer/average molecular weight of themonomer).

[0091] X can be said to be the total number of moles of modifyingresidue introduced by the graft monomer and can be determined by ¹H-NMR.Y is equal to a ratio of the weight average molecular weight (Mw) of thepolymer/the molecular weight of the monomer. In the case ofcopolymerization, the molecular weight of the monomer is defined as anaverage molecular weight of monomers.

[0092] The modified thermoplastic norbornene polymer according to thepresent invention is a graft-modified polymer having a structure thatthe unsaturated compound is bonded to the thermoplastic norbornenepolymer as a backbone polymer by a graft reaction. The repeating unit inthe grafted moiety is determined by the kind of the graft monomer(unsaturated compound).

[0093] The modified thermoplastic norbornene polymers according to thepresent invention feature that (1) the heat resistance and electricalproperties such as dielectric constant are fully excellent, (2) theconcentration of their solutions can be sufficiently heightened, (3)compounding additives can be uniformly dispersed at a high concentrationin their solutions, and the number of kinds of compounding additivescapable of being uniformly dispersed therein can be increased, and (4)since the rate of graft modification is high, prepregs, laminates,interlayer insulating films, overcoats and the like obtained by usingthe modified thermoplastic norbornene polymers are excellent in adhesionproperty (peel strength) to other materials such as metals (metal foils,metallized films, metallic wirings, etc.) and silicon wafers.

[0094] Crosslinking Polymer Composition:

[0095] The crosslinking polymer composition according to the presentinvention features that it contains at least the above-describedmodified thermoplastic norbornene polymer and a crosslinking agent asessential components.

[0096] No particular limitation is imposed on the method forcrosslinking the crosslinking polymer composition according to thepresent invention. For example, the crosslinking can be conducted byusing heat, light, radiation and/or the like. The kind of thecrosslinking agent is suitably selected according to such means. Whenthe above-described modified norbornene polymer is used, the ability touniformly disperse various crosslinking agents therein also becomesgood. Into the crosslinking polymer composition according to the presentinvention, as needed, a crosslinking aid, a flame retardant, othercompounding additives, a solvent, etc. may be blended in addition to thecrosslinking agent.

[0097] (1) Crosslinking Agent:

[0098] In order to crosslink the modified thermoplastic norbornenepolymer according to the present invention, for example, a method ofcrosslinking the polymer by irradiation of radiation is also included.However, a method of crosslinking the polymer by blending a crosslinkingagent is generally adopted. No particular limitation is imposed on thecrosslinking agent. However, {circle over (1)} an organic peroxide,{circle over (2)} a crosslinking agent capable of exhibiting its effectby heat, {circle over (3)} a crosslinking agent capable of exhibitingits effect by light, or the like is used.

[0099] {circle over (1)} Organic Peroxide:

[0100] Examples of the organic peroxide include ketone peroxides such asmethyl ethyl ketone peroxide and cyclohexanone peroxide; peroxyketalssuch as 1,1-bis(t-butyl peroxy)-3,3,5-trimethylcyclohexane and2,2-bis(t-butyl peroxy)butane; hydroperoxides such as t-butylhydroperoxide and 2,5-dimethylhexane-2,5-dihydroperoxide; dialkylperoxides such as dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3 and α,α′-bis(t-butyl peroxy-m-isopropyl)benzene; diacylperoxides such as octanoyl peroxide and isobutyryl peroxide; andperoxyesters such as peroxydicarbonate. Of these, the dialkyl peroxidesare preferred from the viewpoint of performance of the crosslinkedresin. It is preferred to change the kind of the alkyl group accordingto the forming or molding temperature.

[0101] The organic peroxides may be used either singly or in anycombination thereof. The amount of the organic peroxide blended isgenerally 0.001 to 30 parts by weight, preferably 0.01 to 25 parts byweight, more preferably 1 to 20 parts by weight per 100 parts by weightof the modified thermoplastic norbornene polymer. The blending amountwithin this range is preferred because crosslinkability of the resultingcomposition, and properties of the crosslinked resin, such as electricalproperties, chemical resistance and water resistance, are balanced withone another at a high level.

[0102] {circle over (2)} Crosslinking Agent Capable of Exhibiting itsEffect by Heat:

[0103] No particular limitation is imposed on the crosslinking agentcapable of exhibiting its effect by heat so far as it can cause acrosslinking reaction by heating. Examples thereof include aliphaticpolyamines such as diamines, triamines and still higher polyamines,alicyclic polyamines, aromatic polyamines, bisazides, acid anhydrides,dicarboxylic acids, diols, polyhydric phenols and polyamides. Specificexamples thereof include aliphatic polyamines such ashexamethylenediamine, triethylenetetramine, diethylenetriamine andtetraethylenepentamine; alicyclic polyamines such as diaminocyclohexane,3(4),8(9)-bis (aminomethyl)tricyclo-[5,2,1,0^(2,6) ]decane,1,3-(diaminomethyl)cyclohexane, menthenediamine, isophoronediamine,N-aminoethylpiperazine, bis(4-amino-3-methylcyclohexyl)methane andbis(4-amino-cyclohexyl)methane; aromatic polyamines such as4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane,α,α′-bis(4-aminophenyl)-1,3-diisopropylbenzene,α,α′-bis(4-aminophenyl)-1,4-diisopropylbenzene, 4,4′-diaminodiphenylsulfone and m-phenylenediamine; bisazides such as4,4′-bisazidobenzal(4-methyl)cyclohexanone, 4,4′-diazido-chalcone,2,6-bis(4′-azidobenzal)cyclohexanone,2,6-bis-(4′-azidobenzal)-4-methylcyclohexanone, 4,4′-diazido-diphenylsulfone, 4,4′-diazidodiphenylmethane and 2,2′-diazidostilbene; acidanhydrides such as phthalic anhydride, pyromellitic anhydride,benzophenone-tetracarboxylic acid anhydride, nadic anhydride,1,2-cyclohexanedicarboxylic acid and maleic anhydride-modifiedpolypropylene; dicarboxylic acids such as fumaric acid, phthalic acid,maleic acid, trimellitic acid and himic acid; polyhydric phenols such asphenol novolak resins and cresol novolak resin; polyhydric alcohols suchas tricyclodecanediol, diphenylsilanediol, ethylene glycol andderivatives thereof, diethylene glycol and derivatives thereof, andtriethylene glycol and derivatives thereof; and polyamides such as nylon6, nylon 66, nylon 610, nylon 11, nylon 612, nylon 12, nylon 46,methoxymethylated polyamide, polyhexamethylenediamine terephthalamideand polyhexamethylene isophthalamide;.

[0104] These crosslinking agents may be used either singly or in anycombination thereof. Of these, the aromatic polyamines, acid anhydrides,polyhydric phenols and polyhydric alcohols are preferred for reasons ofproviding a crosslinked resin excellent in heat resistance, mechanicalstrength, adhesion property and dielectric properties (low dielectricconstant and dielectric loss tangent). Among others,4,4-diaminodiphenylmethane (aromatic polyamine) and polyhydric alcoholsare particularly preferred.

[0105] No particular limitation is imposed on the amount of thecrosslinking agent blended. From the viewpoints of being able toefficiently conduct a crosslinking reaction and improve the physicalproperties of the resulting crosslinked resin, and being profitable,however, it is generally within a range of 0.001 to 30 parts by weight,preferably 0.01 to 25 parts by weight, more preferably 1 to 20 parts byweight per 100 parts by weight of the modified thermoplastic norbornenepolymer. If the amount of the crosslinking agent is too little, theresulting composition becomes hard to undergo crosslinking, and sosufficient heat resistance and solvent resistance cannot be imparted tothe composition. On the contrary, any amount too great results in acrosslinked resin lowered in properties such as water-absorptionproperty and dielectric properties. It is hence not preferable to usethe crosslinking agent in any amount outside the above range. Therefore,the blending amount within this range is preferred because theseproperties are balanced with one another at a high level.

[0106] As needed, a crosslinking accelerator (hardening accelerator) mayalso be blended to enhance the efficiency of the crosslinking reaction.

[0107] As examples of the hardening accelerator, may be mentioned aminessuch as pyridine, benzyldimethylamine, triethanolamine, triethylamineand imidazoles. The hardening accelerator is added in order to regulatethe rate of the crosslinking reaction and further enhance the efficiencyof the crosslinking reaction. No particular limitation is imposed on theamount of the hardening accelerator blended. However, it is used withina range of generally 0.1 to 30 parts by weight, preferably 1 to 20 partsby weight per 100 parts by weight of the thermoplastic norbornenepolymer. The blending amount within this range is preferred becausecrosslinking density, dielectric properties, water absorption and thelike of the crosslinked resin are balanced with one another at a highlevel. Among others, imidazoles are preferred in that a crosslinkedresin excellent in dielectric properties can be provided.

[0108] {circle over (3)} Crosslinking Agent Capable of Exhibiting itsEffect by Light:

[0109] No particular limitation is imposed on the crosslinking agent(hardener) capable of exhibiting its effect by light so far as it is aphotoreactive substance which reacts with the modified thermoplasticnorbornene polymer by irradiation of actinic rays such as ultravioletrays such as g rays, h rays or i rays, far ultraviolet rays, X rays, orelectron rays to form a crosslinked compound. Examples thereof includearomatic bisazide compounds, photo-induced amine generators andphoto-induced acid generators.

[0110] Specific typical examples of the aromatic bisazide compoundsinclude 4,4′-diazidochalcone, 2,6-bis(4′-azidobenzal)cyclohexanone,2,6-bis(4′-azidobenzal)-4-methylcyclohexanone, 4,4′-diazidodipherLylsulfone, 4,4′-diazidobenzophenone, 4,4′-diazidophenyl,2,7-diazido-fluorene and 4,4′-diazidophenylmethane. These compounds maybe used either singly or in any combination thereof.

[0111] Specific examples of the photo-induced amine generators includeo-nitrobenzyloxycarl)onylcarbamates,2,6-dinitrobenzyloxycarbonylcarbamates andα,α-dimethyl-3,5-dimethoxybenzyloxycarbonylcarbamates of aromatic aminesor aliphatic amines. More specifically, there may be mentionedo-nitrobenzyloxycarbonylcarbamates of aniline, cyclohexylamine,piperidine, hexamethyLenediamine, triethylenetetramine,1,3-(diaminomethyl)cyclohexane, 4,4′-diaminodiphenyl ether,4,4′-diaminodiphenylmethane, phenylenediamine and the like. Thesecompounds may be used either singly or in any combination thereof.

[0112] The photo-induced acid generator is a substance which forms aBrφnsted acid or Lewis acid upon exposure to actinic rays. Examplesthereof include onium salts, halogenated organic compounds,quinonediazide compounds, α,α-bis(sulfonyl)diazomethane compounds,α-carbonyl-α-sulfonyl-diazomethane compounds, sulfone compounds, organicacid ester compounds, organic acid amide compounds and organic acidimide compounds. These compounds, which cleave upon exposure to theactinic rays to form an acid, may be used either singly or in anycombination thereof.

[0113] As examples of other photo-crosslinking agents, may be mentionedbenzoin alkyl ether compounds such as benzoin ethyl ether and benzoinisobutyl ether; benzophenone compounds such as benzophenone,methyl-o-benzoyl benzoate and 4,4¹-dichlorobenzophenone; benzylcompounds such as dibenzyl and benzyl methyl ketal; acetdphenonecompounds such as 2,2-diethoxyacetophenone,2-hydroxy-2-methyl-propiophenone,4-isopropyl-2-hydroxy-2-methyl-propiophenone, 1,1-dichloroacetophenone,2,2-diethoxy-acetophenone and 4′-phenoxy-2,2-dichloroacetophenone;thioxanthone compounds such as 2-chloro-thioxanthone,2-methylthioxanthone and 2-isopropylthioxanthone; anthraquinonecompounds such as 2-ethylanthraquinone, 2-chloroanthraquinone andnaphthoquinone; propiophenone compounds such as2-hydroxy-2-methylpropiophenone and4′-dodecyl-2-hydroxy-2-methylpropioph(none; and organic acid metal saltssuch as cobalt octenate, cobalt naphthenate, manganese octenate andmanganese naphthenate.

[0114] No particular limitation is imposed on the amount of thesephotoreactive compounds blended. From the viewpoints of being able toefficiently conduct the reaction with the modified thermoplasticnorbornene polymer, not impairing the physical properties of theresulting crosslinked resin, and being profitable, however, it isgenerally within a range of 0.001 to 30 parts by weight, preferably 0.01to 25 parts by weight, more preferably 1 to 20 parts by weight per 100parts by weight of the modified thermoplastic norbornene polymer. If theamount of the photoreactive substance added is too little, the resultingcomposition becomes hard to undergo crosslinking, and so sufficient heatresistance and solvent resistance cannot be imparted to the composition.On the other hand, any amount too great results in a crosslinked resinlowered in properties such as water-absorption property and dielectricproperties. It is hence not preferable to use the photoreactive compoundin any amount outside the above range. Therefore, the blending amountwithin this range is preferred because these properties are balancedwith one another at a high level.

[0115] (2) Crosslinking Aid:

[0116] In the present invention, it is preferred to use a crosslinkingaid, because the crosslinkability and the dispersibility of thecompounding additives can be more enhanced.

[0117] No particular limitation is imposed on the crosslinking aid usedin the present invention. Publicly known compounds disclosed in JapanesePatent Application Laid-Open No. 34924/1987 and the like may be used.Examples thereof include oxime nitroso type crosslinking aids such asquinone dioxime, benzoquinone dioxime and p-nitrosophenol; maleimidetype crosslinking aids such as N,N-m-phenylenebismaleimide; allyl typecrosslinking aids such as diallyl phthalate, triallyl cyanurate andtriallyl isocyanurate; methacrylate type crosslinking aids such asethylene glycol dimethacrylate and trimethylolpropane trimethacrylate;and vinyl type crosslinking aids such as vinyltoluene, ethylvinylbenzeneand divinylbenzene. Of these, the allyl type crosslinking aide; andmethacrylate type crosslinking aids are preferred because they make iteasy to uniformly disperse compounding additives.

[0118] The amount of the crosslinking aid added is suitably selectedaccording to the kind of the crosslinking agent used. However, it isgenerally 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weightper part by weight of the crosslinking agent. If the amount of thecrosslinking aid added is too little, the resulting composition becomeshard to undergo crosslinking. On the contrary, any amount too greatresults in a crosslinked resin having a possibility that its electricalproperties, water resistance, moisture resistance and the like may bedeteriorated.

[0119] (3) Flame Retardant:

[0120] The flame retardant is not an essential component. However, it ispreferred that the flame retardant be added to the modifiedthermoplastic norbornene polymer compositions when the composition isused for electronic parts. No particular limitation is imposed on theflame retardant. However, those which undergo none of decomposition,denaturation and deterioration by the crosslinking agent (hardener) arepreferred.

[0121] Various kinds of chlorine- or bromine-containing flame retardantsmay be used as the halogen-containing flame retardants. From theviewpoints of flameproofing effect, heat resistance upon forming ormolding, dispersibility in resins and influence on the physicalproperties of the resins, however, the following flame retardants may bepreferably used. Namely, preferable examples thereof includehexabromobenzine, pentabromo-ethylbenzene, hexabromobiphenyl,decabromodiphenyl, hexabromodiphenyl oxide, octabromodiphenyl oxide,decabromodiphenyl oxide, pentabromocyclohexane, tetrabromobisphenol Aand derivatives thereof [for example, tetrabromobisphenolA-bis(hydroxyethyl ether), tetrabromobisphenol A-bis(2,3-dibromopropylether), tetrabromobisphenol A-bis(bromoethyl ether),tetrabromo-bisphenol A-bis(allyl ether), etc.], tetrabromobisphenol Sand derivative thereof [for example, tetrabromobisphenolS-bis(hydroxyethyl ether), tetrabromobisphenol S-bis(2,3-dibromopropylether), etc.], tetrabromophthalic anhydride and derivatives thereof [forexample, tetrabromophthal-imide, ethylenebistetrabromophthalimide,etc.], ethylene-bis(5,6-dibromonorbornene-2,3-dicarboxyimide),tris-(2,3-dibromopropyl-1) isocyanurate, adducts ofhexabromo-cyclopentadiene by Diels-Alder reaction, tribromophenylglycidyl ether, tribromophenyl acrylate, ethylenebis-tribromophenylether, ethylenebispentabromophenyl ether,tetradecabromodiphenoxybenzene, brominated polystyrene, brominatedpolyphenylene oxide, brominated epoxy resins, brominated polycarbonate,polypentabromobenzyl acrylate, octabromonaphthalene,hexabromocyclododecane, bis(tribromophenyl)fumaramide andN-methylhexabromo-diphenylamine.

[0122] These flame retardants may be used either singly or in anycombination thereof. The amount of the flame retardant added isgenerally 3 to 150 parts by weight, preferably 10 to 140 parts byweight, particularly preferably 15 to 120 parts by weight per 100 partsby weight of the modified thermoplastic norbornene polymer.

[0123] As a flame retardant auxiliary for causing the flame retardant tomore effectively exhibit its flameproofing effect, for example, anantimonial flame retardant auxiliary such as antimony trioxide, antimonypentoxide, sodium antimonate or antimony trichloride may be used. Theseflame retardant auxiliaries are used in a proportion of generally 1 to30 parts by weight, preferably 2 to 20 parts by weight per 100 parts byweight of the flame retardant.

[0124] (4) Filler:

[0125] In order to improve mechanical strength (toughness) and reducecoefficient of linear expansion in particular, a filler may be blendedinto the crosslinking polymer compositions according to the presentinvention. Examples of the filler include inorganic and organic fillers.

[0126] No particular limitation is imposed on the inorganic fillers.Examples thereof include calcium carbonate (precipitated calciumcarbonate, heavy or pulverized calcium, special calcium type fillers),clay (aluminum silicate; fine nepheline syenite powder, calcined clay,silane-modified clay), talc, silica, alumina, diatomaceous earth, quartzsand, pumice powder, pumice balloons, slate powder, mica powder,asbestos, alumina colloid (alumina sol), alumina white, aluminumsulfate, barium sulfate, lithopone, calcium sulfate, molybdenumdisulfide, graphite, glass fibers, glass beads, glass flake, foamedglass beads, fly ash beads, volcanic glass balloons, synthetic inorganicballoons, monocrystalline potassium titanate, carbon fibers, carbonballoons, anthracite culm, artificial cryolite, titanium oxide,magnesium oxide, basic magnesium carbonate, dolomite, potassiumtitanate, calcium, sulfite, mica, asbestos, calcium silicate,montmorillonite, bentonite, graphite, aluminum powder, molybdenumsulfide, boron fibers and silicon carbide fibers.

[0127] Examples of the organic fillers include polyethylene fibers,polypropylene fibers, polyester fibers, polyamide fibers, fluorocarbonfibers, ebonite powder, thermosetting resin balloons, saran balloons,shellac, wood flour, cork powder, polyvinyl alcohol fibers, cellulosepowder and wood pulp.

[0128] (5) Other Compounding Additives:

[0129] To the crosslinking polymer compositions according to the presentinvention, may be added proper amounts of other compounding additivessuch as heat stabilizers, weathering stabilizers, leveling agents,antistatic agents, slip agents, antiblocking agents, anti-foggingagents, lubricants, dyes, pigments, natural oil, synthetic oil and wax,as needed.

[0130] Specific examples thereof includes phenolic antioxidants such astetrakis[methylene-3(3,5-di-t-butyl-4-hydroxyphenyl) propionate]methane,alkyl β-(3,5-di-t-butyl-4-hydroxyphenyl)propionates and2,2′-oxamido-bis[ethyl-3(3,5-di-t-butyl-4-hydroxyphenyl) propionate];phosphoric stabilizers such as trisnonylphenyl phosphite,tris(2,4-di-t-butylphenyl) phosphate and tris(2,4-di-t-butylphenyl)phosphite; fatty acid metal salts such as zinc stearate, calciumstearate and calcium 12-hydroxy-stearate; polyhydric alcohol fatty acidesters such as glycerol monostearate, glycerol monolaurate, glyceroldistearate, pentaerythritol monostearate, pentaerythritol distearate andpentaerythritol tristearate; synthetic hydrotalcite; amine typeantistatic agents; leveling agents for paints, such asfluorine-containing nonionic surfactants, special acrylic resin typeleveling agents and silicone type leveling agents; coupling agents suchas silane coupling agents, titanate coupling agents, aluminum-containingcoupling agents and zircoaluminate coupling agents; plasticizers; andcolorants such as pigments and dyes.

[0131] These compounding additives may be used either singly or in anycombination thereof. The compounding proportions thereof are suitablyselected according to their respective functions and the end applicationintended.

[0132] Into the crosslinking polymer compositions, other kinds ofthermoplastic resins such as polycarbonate, polystyrene, poly(phenylenesulfide), poly(ether imide), polyester, polyamide, polyarylate andpolysulfone; elastomers or rubbery polymers; and the like may be blendedfor the purpose of controlling the mechanical properties and flexibilityof the composition.

[0133] (6) Solvent:

[0134] In the present invention, the modified norbornene polymer may bedissolved in a solvent to prepare an impregnating solution for prepregs,produce a sheet by a solution casting method, or form a film by acoating method.

[0135] In the case where the modified thermoplastic norbornene polymeris dissolved in a solvent, examples of the solvent used include aromatichydrocarbons such as toluene, xylene and ethylbenzene; aliphatichydrocarbons such as n-pentane, hexane and heptane; alicyclichydrocarbons such as cyclohexane; and halogenated hydrocarbons such aschlorobenzene, dichlorobenzene and trichlorobenzene.

[0136] The solvent is used in an amount sufficient to uniformly dissolveor disperse the modified thermoplastic norbornene polymer and theindividual components optionally blended therein.

[0137] Molding, Prepreg, Laminate, Interlayer Insulating Film, etc.:

[0138] The crosslinking polymer composition according to the presentinvention may be molded in the desired form and then crosslinked to forma crosslinked molding. The crosslinking polymer composition is moldedafter dissolving it in a solvent so as not to cause deterioration ofmoldability due to crosslinking in the course of molding, or by meltingit at: a temperature at which it undergoes no crosslinking, orcrosslinking proceeds only at a sufficiently low rate. Specifically, thenorbornene polymer composition dissolved in a solvent is cast, and thesolvent is removed to form a sheet, or a base material is impregnatedwith the composition dissolved in the solvent to conduct molding.

[0139] The crosslinking polymer composition according to the presentinvention can be molded into various parts in accordance with variousmolding processes. Examples of the molding processes in this caseinclude {circle over (1)} a process in which the composition isprocessed into a molding in a state of a thermoplastic resin byinjection molding, press molding, compression molding or the like,{circle over (2)} a process in which a solution with the compositiondissolved in an organic solvent is processed into a molding by pottingor cast molding while removing the solvent, and {circle over (3)} aprocess in which the composition is processed into a thermoset moldingby transfer molding or the like.

[0140] Further, the crosslinking polymer composition according to thepresent invention can be formed into a film by a coating method.

[0141] (1) Prepreg:

[0142] A prepreg which is one of specific examples of the crosslinkedmoldings is produced by uniformly dissolving or dispersing the modifiedthermoplastic norbornene polymer, crosslinking agent and variouscompounding additives in a solvent such as toluene, cyclohexane orxylene, impregnating a reinforcing base material with the solution ordispersion and then drying the base material to remove the solvent. Ingeneral, the prepreg is preferably produced so as to give a thickness ofabout 50 to 500 μm.

[0143] The amount of the solvent used is controlled in such a mannerthat a solids concentration amounts to generally 1 to 90 wt. %,preferably 5 to 85 wt. %, more preferably 10 to 80 wt. %.

[0144] Examples of usable reinforcing base materials include paper basematerials (linter paper, kraft paper, etc.), glass base materials (glasscloth, glass mat, glass paper, quartz fibers, etc.) and synthetic resinfiber base materials (polyester fibers, Aramide fibers, etc.). Thesereinforcing base materials may be surface treated with a treating agentsuch as a silane coupling agent. These reinforcing base materials may beused either singly or in any combination thereof.

[0145] The amount of the modified thermoplastic norbornene polymercomposition to the reinforcing base material is suitably selected asnecessary for the end application intended. However, it is generally 1to 90 wt. %, preferably 10 to 60 wt. % based on the reinforcing basematerial.

[0146] (2) Sheet:

[0147] No particular limitation is imposed on a process for producing asheet. However, a casting process is generally used. For example, thecrosslinking polymer composition according to the present invention isdissolved or dispersed in a solvent such as toluene, xylene orcyclohexane so as to give a solids concentration of about 5 to 50 wt. %,the solution or dispersion is cast or coated on a smooth surface, thesolvent is removed by drying or the like, and the dried product isseparated from the smooth surface to obtain a sheet. When the solvent isremoved by drying, it is preferred to select a method by which foamingby rapid drying does not occur. For example, it is only necessary tovolatilize the solvent to a certain extent at a low temperature and thenraise the temperature so as to sufficiently volatilize the solvent.

[0148] As the smooth surface, may be used a planished metal plate, acarrier film made of a resin, or the like. When the resin-made carrierfilm is used, a solvent to be used and drying conditions are determinedtaking the solvent resistance and heat resistance of a material of thecarrier film into consideration.

[0149] Sheets obtained by the casting process generally have a thicknessof about 10 μm to 1 mm. These sheets can be used as interlayerinsulating films, films for forming moistureproof layers, etc. bycrosslinking them. They may also be used in the production of laminateswhich will be described subsequently.

[0150] (3) Laminate:

[0151] A laminate is obtained by stacking a plurality of theabove-described prepregs and/or uncrosslinked sheets on one another andhot-pressing them, thereby crosslinking and mutually fusion-bonding theminto a necessary thickness. When a laminated sheet is used as a circuitboard, a circuit is formed by, for example, laminating an electricallyconductive layer for wiring composed of a metal foil or the like, oretching the surface. The electrically conductive layer for wiring may belaminated not only on the outer surface of the Laminated sheet as afinished article, but also in the interior of the laminated sheetaccording to the purpose. In order to prevent warpage upon a secondaryprocessing such as etching, it is preferred to laminate laminatingmaterials in combination so as to vertically symmetrize. For example,the surfaces of the stacked prepregs and/or sheets are heated to afusion-bonding temperature according to the modified thermoplasticnorbornene polymer used or higher, generally about 150 to 300° C., andthey are pressed under a pressure of about 30 to 80 kgf/cm², therebycrosslinking and mutually fusion-bonding the respective layers to obtaina laminated sheet.

[0152] Other methods for applying a metal to these insulating layers ora base material include vapor deposition, electroplating, sputtering,ion plating, spraying and layering. Examples of metals commonly usedinclude copper, nickel, tin, silver, gold, aluminum, platinum, titanium,zinc and chromium. Copper is oftenest used in circuit boards.

[0153] (4) Crosslinking:

[0154] In the present invention, a molding is crosslinked by itself orin the form of a laminate to obtain a crosslinked molding. Thecrosslinking may be conducted in accordance with a method known per sein the art. Examples thereof include a method of irradiating a moldingwith radiation, a method of heating a molding to a certain temperatureor higher in the case where an organic peroxide has been blended, and amethod of irradiating a molding with rays such as ultraviolet rays inthe case where a photo-crosslinking agent has been blended. Of these,the method in which the organic peroxide is blended, and the molding isheated to crosslink is preferred, since the method can be conducted withease.

[0155] A temperature at which a crosslinking reaction is caused ismainly determined by a combination of an organic peroxide and acrosslinking aid. However, the crosslinking is conducted by heating amolding to a temperature of generally 80 to 350° C., preferably 120 to300° C., more preferably 150 to 250° C. Crosslinking time is preferablydetermined to be about 4 times as much as the half-life of the organicperoxide, and is generally 5 to 120 minutes, preferably 10 to 90minutes, more preferably 20 to 60 minutes. When a crosslinking agent(hardener) capable of exhibiting its effect by heat is used as thecrosslinking agent, crosslinking is caused by heating. When aphoto-crosslinking agent is used as the crosslinking agent, crosslinkingcan be caused by irradiation of light. When crosslinkable moldings arelaminated and then crosslinked, fusion bonding and crosslinking occurbetween the respective layers, thereby obtaining an integral crosslinkedmolding.

[0156] (5) Crosslinked Molding:

[0157] Examples of crosslinked moldings according to the presentinvention include laminated sheets, circuit boards, interlayerinsulating films and films for forming moistureproof layers. Thecrosslinked moldings according to the present invention generally have awater absorption of at most 0.03%, and a dielectric constant of 2.0 to4.0 and a dielectric loss tangent of 0.0005 to 0.005 as measured at afrequency of 1 MHz. Therefore, the moldings according to the presentinvention are superior in moisture resistance and electrical propertiesto the conventional thermoset moldings. The heat resistance of thecrosslinked moldings according to the present invention is equal to thatof the conventional thermoset moldings. Accordingly, even when alaminated sheet on which a copper foil has been laminated is broughtinto contact with a solder of 260° C. for 30 seconds or with a solder of300° C. for 1 minute, abnormality such as delamination of the metallayer such as the copper foil and/or occurrence of blister is notobserved. In addition, the crosslinked moldings according to the presentinvention are excellent in adhesion property to the copper foil asdemonstrated by a peel strength of generally 1.4 to 2.7 kg/cm² . This isfar improved compared with the conventional thermoplastic norborneneresins. From these results, the laminated sheet which is a crosslinkedmolding according to the present invention is suitable for use as acircuit board.

[0158] Moldings obtained by using the crosslinking polymer compositionsaccording to the present invention as thermoplastic resins are useful aselectronic parts such as connectors, relays and capacitors; electronicparts such as injection-molded sealing parts for semiconductor devicessuch as transistors, ICs and LSIs; and body tubes for optical lenses andparts such as polygon mirrors and Fθ mirrors.

[0159] When the crosslinking polymer compositions according to thepresent invention are used in a state dissolved in an organic solvent,they are useful for uses such as sealing materials for potting and castmolding.

[0160] When the crosslinking polymer compositions according to thepresent invention are used as transfer molding materials, they areuseful as packaging (sealing) materials for semiconductor devices.

[0161] The crosslinking polymer compositions according to the presentinvention can be used in the form of a film. In the case where they areused as films, there are cases {circle over (1)} where the crosslinkingpolymer composition is dissolved in an organic solvent, and the solutionis formed into a film by a casting process or the like in advance to useit, and {circle over (2)} where the solution is applied, and the solventis then removed to use a film formed as an overcoat. More specifically,such films are useful as, for example, insulating sheets for laminatedsheets, interlayer insulating films, liquid sealing materials forsemiconductor devices, overcoating materials, etc.

EXAMPLES

[0162] The present invention will hereinafter be described specificallyby the following Examples and Comparative Examples. Incidentally,physical properties were measured in accordance with the followingmethods:

[0163] (1) The glass transition temperature was measured in accordancewith the differential scanning calorimetry (DSC method).

[0164] (2) The molecular weight was determined in terms of polystyreneas measured by gel permeation chromatography (GPC) using toluene as asolvent unlese; expressly noted.

[0165] (3) The rates of hydrogenation in the main chain and side chainwere determined by ¹H-NMR.

[0166] (4) The total number of moles of modifying residue introduced byan unsaturated epoxy compound or unsaturated carboxylic compound wasdetermined by ¹H-NMR, and the rate of graft modification was calculatedout in accordance with the above-described equation.

[0167] (5) The flame retardancy was determined in accordance with the USUL-94 test standard.

[0168] (6) The dielectric constant and dielectric loss tangent weredetermined at 1 MHz in accordance with JIS K 6911.

[0169] (7) The copper foil peeling strength was determined in thefollowing manner. Namely, a specimen 20 mm wide and 100 mm long was cutout of a resin laminate sample, parallel notches were cut at an intervalof 10 mm in the copper foil surface of the specimen, and the copper foilwas continuously peeled off at a rate of 50 mm/min in a directionperpendicular to the surface by a tensile tester. The copper foilpeeling strength was expressed in terms of the minimum stress value atthis time.

[0170] (8) The adhesion property was determined by conducting across-cut peel strength test in accordance with JIS K 5400.

[0171] (9) The durability was determined by leaving a test sample tostand for 1,000 hours under conditions of 90° C. and 95% relativehumidity to observe whether visual abnormality such as blister, thecorrosion and/or tarnishing of copper, and the like occurred or not.

[0172] (10) The heat resistance was determined in the following manner.After a test sample was brought into contact with a solder of 300° C.for 1 minute, the appearance of the sample was observed to evaluate itin accordance with the following standard:

[0173] Good: Neither delamination nor blister was observed;

[0174] Poor: Delamination or blister was observed.

Example 1

[0175] A 1-liter flask purged with nitrogen was charged with 5 g of8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-3-dodecene (i.e.,6-methyl-1,4:5,8-dimethano-1,4,4a,5,6,7,8,8a-octahydronaphthalene;hereinafter referred to as “ETD”) and 120 g of toluene, followed byaddition of 0.287 mmol of triisobutylaluminum and 0.287 mmol of isobutylalcohol as polymerization catalysts, and 3.83 mmol of 1-hexene as amolecular weight modifier. To the mixture, 0.057 mmol of tungstenhexachloride was added, and stirring was conducted at 40° C. for 5minutes. Thereafter, 45 g of ETD and 0.086 mmol of tungsten hexachloridewere continuously added dropwise to the reaction system over about 30minutes. After completion of the addition, stirring was continued foradditional 30 minutes to complete polymerization.

[0176] This polymerization reaction mixture was transferred to a 1-literautoclave, and 160 g of toluene were added thereto. After a mixture of0.5 g of nickel acetylacetonate and 5.15 g of a 30 wt. % toluenesolution of triisobutylaluminum was then added, and the interior of theautoclave was purged with hydrogen, the contents were heated to 80° C.with stirring. The hydrogen pressure was raised to 30 kg/cm² at the timethe temperature was stable, thereby conducting a reaction for 3 hourswhile supplying hydrogen consumed in the course of the reaction. Then,4.2 g of water and 2.5 g of activated alumina (specific surface area:320 cm²/g; pore volume: 0.8 cm³/g; average particle size: 15 μm; NeobeadD powder, product of Mizusawa Industrial Chemicals, Inc.) were added tothe reaction mixture, followed by stirring at 80° C. for 1 hour. Solidswere then removed by filtration, and the resultant hydrogenationreaction mixture was poured into 3 liters of isopropyl alcohol todeposit a resin formed. The resin was collected by filtration and thendried for 48 hours at 100° C. under 1 Torr or lower.

[0177] Fifty parts by weight of the thus-obtained polymer were mixedwith 30 parts by weight of allyl glycidyl ether, 3.0 parts by weight ofdicumyl peroxide and 120 parts by weight of t-butylbenzene to conduct areaction at 150° C. for 3 hours in an autoclave. The reaction mixturewas then solidified and dried in the same manner as described above toobtain epoxy-modified Polymer (A). The result of the synthesis is shownin Table 1.

Example 2

[0178] Epoxy-modified Polymer (B) was obtained in the same manner as inExample 1 except that the amount of 1-hexene was changed from 3.83 mmolto 5.75 mmol. The result of the synthesis is shown in Table 1.

Example 3

[0179] Maleic anhydride-modified Polymer (C) was obtained in the samemanner as in Example 1 except that allyl glycidyl ether was changed tomaleic anhydride. The result of the synthesis is shown in Table 1.

Example 4

[0180] Maleic anhydride-modified Polymer (D) was obtained in the samemanner as in Example 1 except that the amount of 1-hexene was changedfrom 3.83 mmol to 5.75 mmol, and allyl glycidyl ether was changed tomaleic anhydride. The result of the synthesis is shown in Table 1.

Example 5

[0181] Epoxy-modified Polymer (E) was obtained in the same manner as inExample 1 except that ETD was changed totricyclo[4.3.0.1^(2,5)]-3,7-decadiene (i.e., dicyclo-pentadiene;hereinafter referred to as “DCP”), and the amounts of allyl glycidylether and dicumyl peroxide were changed to from 30 parts by weight to100 parts by weight and from 3.0 parts by weight to 10 parts by weight,respectively. The result of the synthesis is shown in Table 1.

Example 6

[0182] Epoxy-modified Polymer (F) was obtained in the same manner as inExample 1 except that the amount of 1-hexene was changed from 3.83 mmolto 5.75 mmol, ETD was changed to DCP, and the amounts of allyl glycidylether and dicumyl peroxide were changed to from 30 parts by weight to100 parts by weight and from 3.0 parts by weight to 10 parts by weight,respectively. The result of the synthesis is shown in Table 1.

Example 7

[0183] Maleic anhydride-modified Polymer (G) was obtained in the samemanner as in Example 1 except that ETD was changed to DCP, 30 parts byweight of allyl glycidyl ether were changed to 100 parts by weight ofmaleic anhydride, and the amount of dicumyl peroxide was, changed from3.0 parts by weight to 10 parts by weight. The result of the synthesisis shown in Table 1.

Example 8

[0184] Maleic anhydride-modified Polymer (H) was obtained in the samemanner as in Example 1 except that the amount of 1-hexene was changedfrom 3.83 mmol to 5.75 mmol, ETD was changed to DCP, 30 parts by weightof allyl glycidyl ether were changed to 100 parts by weight of maleicanhydride, and the amount of dicumyl peroxide was changed from 3.0 partsby weight to 10 parts by weight. The result of the synthesis is shown inTable 1.

Example 9

[0185] Epoxy-modified Polymer (I) was obtained in the same manner as inExample 1 except that ETD was changed to1,4-methano-1,4,4a,9a-tetrahydrofluorene (hereinafter referred to as“MTF”), and the amount of allyl glycidyl ether was changed to from 30parts by weight to !50 parts by weight. The result of the synthesis isshown in Table 1.

Example 10

[0186] Epoxy-modified Polymer (J) was obtained in the same manner as inExample 1 except that the amount of 1-hexene was changed from 3.83 mmolto 5.75 mmol, ETD was changed to MTF, and the amount of allyl glycidylether was changed to from 30 parts by weight to 50 parts by weight. Theresult of the synthesis is shown in Table 1.

Example 11

[0187] Maleic anhydride-modified Polymer (K) was obtained in the samemanner as in Example 1 except that ETD was changed to MTF, and 30 partsby weight of allyl glycidyl ether were changed to 50 parts by wei(ht ofmaleic anhydride. The result of the synthesis is shown in Table 1.

Example 12

[0188] Maleic anhydride-modified Polymer (L) was obtained in the samemanner as in Example 1 except that the amount of 1-hexene was changedfrom 3.83 mmol to 5.75 mmol, ETD was changed to MTF, and 30 parts byweight of allyl glycidyl ether were changed to 50 parts; by weight ofmaleic anhydride. The result of the synthesis is shown in Table 1. TABLE1 Hydrogena- Hydrogena- Modifi- Polymer Polymer- tion rate of tion rateof Molecular weight Modify- cation Molecular weight comp'n ization mainchain nucleus Tg after hydrog'n ing rate Tg after modif. Code (wt. %)method (%) (%) (° C.) Mn × 10⁴ Mw × 10⁴ group (%) (° C.) Mn × 10⁴ Mw ×10⁴ No. Ex. 1 ETD Ring- ≧99 — 138 1.85 3.16 Epoxy 17 164 1.75 2.99 A(100) opening Ex. 2 ETD Ring- ≧99 — 132 0.81 1.34 Epoxy 24 164 0.70 1.28B (100) opening Ex. 3 ETD Ring- ≧99 — 138 1.85 3.16 Maleic 16 159 1.913.22 C (100) opening Ex. 4 ETD Ring- ≧99 — 132 0.81 1.34 Maleic 23 1610.98 1.69 D (100) opening Ex. 5 DCP Ring- ≧99 — 94 1.66 2.81 Epoxy 19122 1.51 2.66 E (100) opening Ex. 6 DCP Ring- ≧99 — 87 0.69 1.24 Epoxy30 132 0.50 0.91 F (100) opening Ex. 7 DCP Ring- ≧99 — 94 1.66 2.81Maleic 19 119 1.80 3.03 G (100) opening Ex. 8 DCP Ring- ≧99 — 87 0.691.24 Maleic 28 126 0.96 1.51 H (100) opening Ex. 9 MTF Ring- ≧99 ≈0 1351.75 2.91 Epoxy 21 161 1.32 2.18 I (100) opening Ex. 10 MTF Ring- ≧99 ≈0128 0.79 1.43 Epoxy 28 163 0.55 0.95 J (100) opening Ex. 11 MTF Ring-≧99 ≈0 135 1.75 2.91 Maleic 19 154 1.68 2.79 K (100) opening Ex. 12 MTFRing- ≧99 ≈0 128 0.79 1.43 Maleic 23 154 0.85 1.54 L (100) opening

Comparative Example 1

[0189] An unmodified hydrogenated product was synthesized in the samemanner as in Example 1. The thus-obtained product is referred to asPolymer (M). The result of the synthesis is shown in Table 2.

Comparative Example 2

[0190] Epoxy-modified Polymer (N) was obtained in the same manner as inExample 1 except that the amount of allyl glycidyl ether was changedfrom 30 parts by weight to 3 parts by weight. The result of thesynthesis is shown in Table 2.

Comparative Example 3

[0191] Maleic anhydride-modified Polymer (0) was obtained in the samemanner as in Example 1 except that 30 parts by weight of allyl glycidylether were changed from to 3 parts by weight maleic anhydride. Theresult of the synthesis is shown in Table 2.

Comparative Example 4

[0192] An unmodified hydrogenated product was synthesized in the samemanner as in Example 5. The thus-obtained product is referred to asPolymer (P). The result of the synthesis is shown in Table 2.

Comparative Example 5

[0193] Epoxy-modified Polymer (Q) was obtained in the same manner as inExample 5 except that the amounts of allyl glycidyl ether and dicumylperoxide were changed from 100 parts by weight to 15 parts by weight andfrom 10 parts by weight to 1.0 part by weight, respectively. The resultof the synthesis is shown in Table 2.

Comparative Example 6

[0194] Maleic anhydride-modified Polymer (R) was obtained in the samemanner as in Example 5 except that the amounts of maleic anhydride anddicumyl peroxide were changed from 100 parts by weight to 15 parts byweight and from 10 parts by weight to 1.0 part by weight, respectively.The result of the synthesis is shown in Table 2.

Comparative Example 7

[0195] An unmodified hydrogenated product was synthesized in the samemanner as in Example 9. The thus-obtained product is referred to asPolymer (S). The result of the synthesis is shown in Table 2.

Comparative Example 8

[0196] Epoxy-modified Polymer (T) was obtained in the same manner as inExample 9 except that the amounts of allyl glycidyl ether and dicumylperoxide were changed from 50 parts by weight to 10 parts by weight andfrom 3.0 parts by weight to 1.0 part by weight, respectively. The resultof the synthesis is shown in Table 2.

Comparative Example 9

[0197] Maleic anhydride-modified Polymer (U) was obtained in the samemanner as in Example 11 except that the amounts of maleic anhydride anddicumyl peroxide were changed from 50 parts by weight to 10 parts byweight and from 3.0 parts by weight to 1.0 part by weight, respectively.The result of the synthesis is shown in Table 2.

Comparative Example 10

[0198] An unmodified hydrogenated product was synthesized in the samemanner as in Example 1 except that the amount of 1-hexene was changedfrom 3.83 mmol to 2.30 mmol. The thus-obtained product is referred to asPolymer (V). The result of the synthesis is shown in Table 2. TABLE 2Hydrogena- Hydrogena- Modifi- Polymer Polymer- tion rate of tion rate ofMolecular weight Modify- cation Molecular weight comp'n ization mainchain nucleus Tg after hydrog'n ing rate Tg after modif. Code (wt. %)method (%) (%) (° C.) Mn × 10⁴ Mw × 10⁴ group (%) (° C.) Mn × 10⁴ Mw ×10⁴ No. Comp. ETD Ring- ≧99 — 138 1.85 3.16 — — — — — M Ex. 1 (100)opening Comp. ETD Ring- ≧99 — 138 1.85 3.16 Epoxy 5 150 1.80 3.10 N Ex.2 (100) opening Comp. ETD Ring- ≧99 — 138 1.85 3.16 Maleic 6 151 1.813.15 O Ex. 3 (100) opening Comp. DCP Ring- ≧99 — 94 1.66 2.81 — — — — —P Ex. 4 (100) opening Comp. DCP Ring- ≧99 — 94 1.66 2.81 Epoxy 7 1151.58 2.77 Q Ex. 5 (100) opening Comp. DCP Ring- ≧99 — 94 1.66 2.18Maleic 7 109 1.70 2.98 R Ex. 6 (100) opening Comp. MTF Ring- ≧99 ≈0 1351.75 2.91 — — — — — S Ex. 7 (100) opening Comp. MTF Ring- ≧99 ≈0 1351.75 2.91 Epoxy 5 145 1.60 2.71 T Ex. 8 (100) opening Comp. MTF Ring-≧99 ≈0 135 1.75 2.91 Maleic 4 143 1.70 2.85 U Ex. 9 (100) opening Comp.ETD Ring- ≧99 — 140 2.85 5.78 — — — — — V Ex. 10 (100) opening

Examples 13 to 24

[0199] The individual modified polymers obtained in Examples 1 to 12 andvarious kinds of components were blended so as to give theircorresponding compositions shown in Table 3, and the thus-obtainedcompositions were separately dissolved in toluene to give a solidsconcentration of 50 to 60 wt. %, thereby preparing respective varnishes.After these solutions were left at rest for 30 minutes, uniformity ofthe solutions was visually evaluated to rank them in accordance with thefollowing standard:

[0200] Uniformity of Solution:

[0201] ∘: The solution was completely uniform; and

[0202] ×: The solution underwent phase separation.

[0203] An E glass cloth 10 cm wide, 10 cm long and about 0.5 mm thickwas dipped for 10 seconds in each of these solutions, slowly pulled upand then left to stand for 1 minute. Only solids in theresin-impregnated glass cloth thus obtained were dissolved again intoluene, and the resultant solution was poured into a large amount ofisopropyl acetate to solidify a modified polymer portion. The solidifiedpolymer was collected by filtration. On the other hand, the filtrate waspoured into a large amount of methanol to collect a flame retardantportion in the same manner as described above.

[0204] These portions were separately dried for 48 hours at 70° C. under1 Torr to measure their weights. The uniformity of impregnation wasevaluated on the basis of a difference between a weight ratio of the twocomponents at this time and a weight ratio of the two components in astate of the varnish to rank it in the following standard:

[0205] Uniformity of Impregnation:

[0206] ⊚: The difference in weight ratio was lower than 2%;

[0207] ∘: The difference in weight ratio was not lower than 2%, butlower than 5%;

[0208] Δ: The difference in weight ratio was not lower than 5t, butlower than 10%; and

[0209] ×: The difference in weight ratio was not lower than 10%.

[0210] Further, an E glass cloth was dipped in and impregnated with eachof the above solutions and then dried in an air oven to prepare acurable composite material (prepreg). The weight of the base material inthe prepreg was controlled to 40% based on the weight of the prepreg. Asneeded, plural sheets of the thus-produced prepreg were stacked on oneanother so as to give a thickness of 0.8 mm after molding, and a copperfoil 35 μm thick was placed on both sides thereof. The thus-obtainedlaminate was molded and cured by a hot: pressing machine to obtain aresin laminate.

[0211] Various physical properties of the resin laminates obtained insuch a manner were measured. As a result, all the resin laminatesexhibited good dielectric constant and copper foil peeling strength andhad flame retardancy of V-0. TABLE 3 Copper Cross- foil linking FlameSolids Dielec. peeling Polymer Peroxide aid retardant Hardener conc'nUniformity const. strength (part) (part) (part) (part) (part) (%)Solution Impregnation ε (kg/cm²) Ex.13 A (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.05 2.0 Ex.14 B (60) a (1) TAIC (5) b (40)Imidazole (1) 60 ◯ ⊚ 3.10 2.3 Ex.15 C (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.00 1.9 Ex.16 D (60) a (1) TAIC (5) b (40)Imidazole (1) 60 ◯ ⊚ 3.05 2.1 Ex.17 E (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.00 2.0 Ex.18 F (60) a (1) TAIC (5) b (40)Imidazole (1) 60 ◯ ⊚ 3.15 2.6 Ex.19 G (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.00 2.1 Ex.20 H (60) a (1) TAIC (5) b (40)Imidazole (4) 60 ◯ ⊚ 3.10 2.5 Ex.21 I (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.05 2.1 Ex.22 G (60) a (1) TAIC (5) b (40)Imidazole (1) 60 ◯ ⊚ 3.05 2.3 Ex.23 K (60) a (1) TAIC (5) b (40)Imidazole (1) 50 ◯ ⊚ 3.00 1.8 Ex.24 L (60) a (1) TAIC (5) b (40)Imidazole (1) 60 ◯ ⊚ 3.05 2.2

[0212] (Note)

[0213] Peroxide: a=2,5-Dimethyl-2,5-di(t-butyl peroxy)hexyne-3;

[0214] Crosslinking aid: TAIC=Triallyl isocyanurate;

[0215] Flame retardant: b=Brominated bisphenl A type epoxy resin (AER8010, product of Asahi-CIBA Limited; Br content: 5 wt. %);

[0216] Hardener: Imidazole=2-Ethyl-4-methylimidazole.

[0217] It is understood from Table 3 that even when the modifiedpolymers (Examples 13 to 24) according to the present invention areprepared into solutions at a solids concentration of 50 to 60 wt. %, thecompounding additives such as the crosslinking agent, crosslinking aid,flame retardant and hardener can be uniformly dispersed therein, and theresultant moldings are excellent in both dielectric constant and copperfoil peeling strength.

Comparative Examples 11 to 20

[0218] Respective experiments were conducted in the same manner as inExamples 13 to 24 except that the modified or unmodified polymersobtained in Comparative Examples 1 to 10 were used in place of themodified polymers obtained in Examples 1 to 12. The results are shown inTable 4. TABLE 4 Copper Cross- foil linking Flame Solids Dielec. peelingPolymer Peroxide aid retardant Hardener conc'n Uniformity const.strength (part) (part) (part) (part) (part) (%) Solution Impregnation ε(kg/cm²) Comp. M (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.900.6 Ex. 11 Comp. N (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 12 Comp. O (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 13 Comp. P (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.900.6 Ex. 14 Comp. Q (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 15 Comp. R (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 16 Comp. S (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.900.6 Ex. 17 Comp. T (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 18 Comp. U (60) a (1) TAIC (5) b (40) Imidazole (1) 50 ◯ ⊚ 2.951.0 Ex. 19 Ex. 20 V (60) a (1) TAIC (5) b (40) Imidazole (1) 50 X X 2.900.6

[0219] It is understood from the results shown in Table 4 that theunmodified polymers and the modified polymer low in modification rateexhibit insufficient copper foil peeling strength.

Example 25

[0220] Epoxy-modified Polymer (a) was obtained in the same manner as inExample 1 except that the amount of 1-hexene was changed from 3.83 mmolto 1.86 mmol. The result of the synthesis is shown in Table 5.

Example 26

[0221] Maleic anhydride-modified Polymer (b) was obtained in the samemanner as in Example 25 except that 30 parts by weight of allyl glycidylether were changed to 30 parts by weight of maleic anhydride. The resultof the synthesis is shown in Table 5.

Example 27

[0222] Epoxy-modified Polymer (c) was obtained in the same manner as inExample 25 except that ETD was changed to DCP, and the amounts of allylglycidyl ether and dicumyl peroxide were changed from 30 parts by weightto 100 parts by weight and from 3.0 parts by weight to 10 parts byweight, respectively. The result of the synthesis is shown in Table 5.

Example 28

[0223] Maleic anhydride-modified Polymer (d) was obtained in the samemanner as in Example 27 except that allyl glycidyl ether was changed tomaleic anhydride. The result of the synthesis is shown in Table 5.

Example 29

[0224] Epoxy-modified Polymer (e) was obtained in the same manner as inExample 25 except that ETD was changed to MTF, and the amount of allylglycidyl ether was changed from 30 parts by weight to 50 parts byweight. The result of the synthesis is shown in Table 5.

Example 30

[0225] Maleic anhydride-modified Polymer (f) was obtained in the samemanner as in Example 29 except that allyl glycidyl ether was changed tomaleic anhydride. The result of the synthesis is shown in Table 5.

Comparative Example 21

[0226] An unmodified hydrogenated product was synthesized in the samemanner as in Example 25. The thus-obtained product is referred to asPolymer (g). The result of the synthesis is shown in Table 5.

Comparative Example 22

[0227] Epoxy-modified Polymer (h) was obtained in the same manner as inExample 25 except that the amount of allyl glycidyl ether was changedfrom 30 parts by weight to 3.0 parts by weight. The result of thesynthesis is shown in Table 5.

Comparative Example 23

[0228] Maleic anhydride-modified (i) was obtained in the same manner asin Example 26 except that the amount of maleic anhydride was changedfrom 30 parts by weight to 3.0 parts by weight. The result of thesynthesis is shown in Table 5.

Comparative Example 24

[0229] An unmodified hydrogenated product was synthesized in the samemanner as in Example 27. The thus-obtained product is referred to asPolymer (j). The result of the synthesis is shown in Table 5.

Comparative Example 25

[0230] Epoxy-modified Polymer (k) was obtained in the same manner as inExample 27 except that the amount of allyl glycidyl ether was changedfrom 100 parts by weight to 15 parts by weight. The result of thesynthesis is shown in Table 5.

Comparative Example 26

[0231] Maleic anhydride-modified (1) was obtained in the same manner asin Example 28 except that the amount of maleic anhydride was changedfrom 100 parts by weight to 15 parts by weight. The result of thesynthesis is shown in Table 5.

Comparative Example 27

[0232] An unmodified hydrogenated product was synthesized in the samemanner as in Example 29. The thus-obtained product is referred to asPolymer (m). The result of the synthesis is shown in Table 5.

Comparative Example 28

[0233] Epoxy-modified Polymer (n) was obtained in the same manner as inExample 29 except that the amount of allyl glycidyl ether was changedfrom 50 parts by weight to 10 parts by weight. The result of thesynthesis is shown in Table 5.

Comparative Example 29

[0234] Maleic anhydride-modified (o) was obtained in the same manner asin Example 30 except that the amount of maleic anhydride was changedfrom 50 parts by weight to 10 parts by weight. The result of thesynthesis is shown in Table 5. TABLE 5 Hydrogena- Hydrogena- Modifi-Polymer Polymer- tion rate of tion rate of Molecular weight Modify-cation Molecular weight comp'n ization main chain nucleus Tg afterhydrog'n ing rate Tg after modif. Code (wt. %) method (%) (%) (° C.) Mn× 10⁴ Mw × 10⁴ group (%) (° C.) Mn × 10⁴ Mw × 10⁴ No. Ex. 25 ETD Ring-≧99 — 140 2.45 4.54 Epoxy 17 164 2.40 4.41 a (100) opening Ex. 26 ETDRing- ≧99 — 140 2.45 4.54 Maleic 26 161 2.60 4.68 b (100) opening Ex. 27DCP Ring- ≧99 — 95 2.11 4.45 Epoxy 15 122 2.06 4.31 c (100) opening Ex.28 DCP Ring- ≧99 — 95 2.11 4.45 Maleic 16 119 2.24 4.60 d (100) openingEx. 29 MTF Ring- ≧99 ≈0 135 2.20 4.43 Epoxy 21 161 2.08 4.30 e (100)opening Ex. 30 MTF Ring- ≧99 ≈0 135 2.20 4.43 Maleic 19 154 2.28 4.61 f(100) opening Comp. ETD Ring- ≧99 — 140 2.45 4.54 — — — — — g Ex. 21(100) opening Comp. ETD Ring- ≧99 — 140 2.45 4.54 Epoxy 5 151 2.40 4.46h Ex. 22 (100) opening Comp. ETD Ring- ≧99 — 140 2.45 4.54 Maleic 5 1442.51 4.57 i Ex. 23 (100) opening Comp. DCP Ring- ≧99 — 95 2.11 4.45 — —— — — j Ex. 24 (100) opening Comp. DCP Ring- ≧99 — 95 2.11 4.45 Epoxy 6115 2.08 4.37 k Ex. 25 (100) opening Comp. DCP Ring- ≧99 — 95 2.11 4.45Maleic 7 109 2.15 4.50 l Ex. 26 (100) opening Comp. MTF Ring- ≧99 ≈0 1352.20 4.43 — — — — — m Ex. 27 (100) opening Comp. MTF Ring- ≧99 ≈0 1352.20 4.43 Epoxy 4 145 2.16 4.35 n Ex. 28 (100) opening Comp. MTF Ring-≧99 ≈0 135 2.20 4.43 Maleic 5 142 2.21 4.47 o Ex. 29 (100) opening

Examples 31 to 36

[0235] Thirty parts by weight of each of the modified polymers obtainedin Examples 25 to 30 and 1.2 parts by weight ofbisazidobenzal(4-methyl)cyclohexanone were dissolved in 100 parts byweight of xylene. Each composition was provided as a uniform solutionwithout forming any precipitate.

[0236] This uniform solution was then coated on a silicon wafer, inwhich an aluminum wiring had been formed on an SiO₂ film 4000 Å thick,by a spin coating process, and the thus-coated solution was prebaked at90° C. for 60 seconds, thereby forming a coating film 3.3 μm Thick onthe aluminum wiring. Each sample thus obtained was cured at 250° C. for3 hours under nitrogen, thereby forming an overcoat 3 μm thick toevaluate it as to dielectric constant, adhesion property, soldering heatresistance and durability (heat resistance and moisture resistance). Theresults are shown in Table 6.

Comparative Examples 30 to 38

[0237] Respective experiments were conducted in the same manner as inExamples 25 to 30 except that the modified or unmodified polymersobtained in Comparative Examples 21 to 29 were used in place of themodified polymers obtained in Examples 25 to 30. The results are shownin Table 6. TABLE 6 Adhesion Change in property metal layer Solderingalumin. wiring- after Dielec. Dielec. heat formed silicon surabilityloss const. Code resistance wafer test tangent (1 MHz) No. Ex. 31 Good100/100 Not changed 0.0009 2.3 a Ex. 32 Good 100/100 Not changed 0.00092.3 b Ex. 33 Good 100/100 Not changed 0.0007 2.2 c Ex. 34 Good 100/100Not changed 0.0007 2.2 d Ex. 35 Good 100/100 Not changed 0.0009 2.3 eEx. 36 Good 100/100 Not changed 0.0009 2.3 f Comp. Poor 5/100 Corrodedand 0.0007 2.2 g Ex. 30 tarnished Comp. Partially 20/100 Not changed0.0009 2.3 h Ex. 31 deformed Comp. Partially 20/100 Not changed 0.00092.3 i Ex. 32 deformed Comp. Poor 3/100 Corroded and 0.0007 2.2 Ex. 33tarnished Comp. Partially 20/100 Not changed 0.0007 2.2 k Ex. 34deformed Comp. Partially 20/100 Not changed 0.0007 2.2 l Ex. 35 deformedComp. Poor 5/100 Corroded and 0.0007 2.2 m Ex. 36 tarnished Comp.Partially 20/100 Not changed 0.0009 2.3 n Ex. 37 deformed Comp.Partially 20/100 Not changed 0.0009 2.3 o Ex. 38 deformed

[0238] It is understood from the results shown in Table 6 that when themodified polymers according to the present invention are used, overcoats(or interlayer insulating films) excellent in soldering heat resistance,adhesion property, durability, electrical properties and the like can beobtained.

Industrial Applicability

[0239] According to the present invention, there are provided modifiedthermoplastic norbornene polymers excellent in electrical propertiessuch as dielectric constant and dielectric loss tangent and also inadhesion property to other materials such as metals and silicon wafers,a production process thereof, crosslinking polymer compositionscomprising such a modified thermoplastic norbornene polymer and acrosslinking agent, moldings thereof, and sheets, prepregs, laminatesand the like using such a composition. The modified thermoplasticnorbornene polymers and compositions comprising such a polymer accordingto the present invention can be applied to a wide variety of fields suchas circuits boards, interlayer insulating films, semiconductor devicesand electronic parts in precision apparatus such as electronic computersand communication machines.

1. A modified thermoplastic norbornene polymer obtained bygraft-modifying a thermoplastic norbornene polymer selected from aring-opening polymer of a norbornene monomer or a hydrogenated productthereof with at least one unsaturated compound selected from the groupconsisting of unsaturated epoxy compounds and unsaturated carboxyliccompounds, wherein the modified polymer has a rate of graft modificationof at least 10 molt and a number average molecular weight (Mn) of 500 to500,000.
 2. The modified thermoplastic norbornene polymer according toclaim 1, wherein the thermoplastic norbornene polymer is a polymerhaving repeating units represented by the formula (A):

wherein R¹ to R⁸ are independently a hydrogen atom, hydrocarbon group,halogen atom, alkoxy group, ester group, cyano group, amide group, imidegroup, silyl group or hydrocarbon group substituted by a polar group(i.e., a halogen atom, alkoxy group, ester group, cyano group, amidegroup, imide group or silyl group), with the proviso that at least twoof R⁵ to R⁸ may be bonded to each other to form a monocycle orpolycycle, the monocycle or polycycle may have carbon-carbon doublebond(s) or be in the form of an aromatic ring, and R⁵ and R⁶, or R⁷ andR⁸ may form an alkylidene group, and . . . means either a single bond ora double bond.
 3. The modified thermoplastic norbornene polymeraccording to claim 1 or 2, wherein the rate of graft modification is 10to 100 molt.
 4. The modified thermoplastic norbornene polymer accordingto claim 1 or 2, wherein the rate of graft modification is 15 to 50 mol%.
 5. The modified thermoplastic norbornene polymer according to any oneof claims 1 and 4, wherein the number average molecular weight (Mn)falls within a range of 500 to 20,000.
 6. The modified thermoplasticnorbornene polymer according to any one of claims 1 and 4, wherein thenumber average molecular weight (Mn) falls within a range of from higherthan 20,000 to not higher than 500,000.
 7. A process for producing amodified thermoplastic norbornene polymer having a rate of graftmodification of at least 10 molt and a number average molecular weight(Mn) of 500 to 500,000, the process comprising reacting a thermoplasticnorbornene polymer selected from a ring-opening polymer of a norbornenemonomer or a hydrogenated product thereof and having a number averagemolecular weight (Mn) of 500 to 500,000 with at least one unsaturatedcompound selected from the group consisting of unsaturated epoxycompounds and unsaturated carboxylic compounds in the presence of anorganic peroxide.
 8. A crosslinking polymer composition comprising amodified thermoplastic norbornene polymer obtained by graft-modifying athermoplastic norbornene polymer selected from a ring-opening polymer ofa norbornene monomer or a hydrogenated product thereof with at least oneunsaturated compound selected from the group consisting of unsaturatedepoxy compounds and unsaturated carboxylic compounds, and having a rateof graft modification of at least 10 mol % and a number averagemolecular weight (Mn) of 500 to 500,000, and a crosslinking agent. 9.The crosslinking polymer composition according to claim 8, wherein thecrosslinking agent is selected from {circle over (1)} an organicperoxide, {circle over (2)} a crosslinking agent capable of exhibitingits effect by heat or {circle over (3)} a crosslinking agent capable ofexhibiting its effect by light.
 10. The crosslinking polymer compositionaccording to claim 8 or 9, wherein the crosslinking agent is containedin a proportion of 0.001 to 30 parts by weight per 100 parts by weightof the modified thermoplastic norbornene polymer.
 11. The crosslinkingpolymer composition according to any one of claims 8 to 10, whichfurther comprises a crosslinking aid.
 12. The crosslinking polymercomposition according to any one of claims 8 to 11, which furthercomprises a flame retardant.
 13. A molding obtained by molding thecrosslinking polymer composition according to any one of claims 8 to 12.14. A laminate having a structure that a layer formed of thecrosslinking polymer composition according to any one of claims 8 to 12is laminated on a metal layer.
 15. A prepreg comprising a reinforcingbase material impregnated with the crosslinking polymer compositionaccording to any one of claims 8 to 12.